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: http://rtm-cs.sinp.msu.ru/manual/howto/PostgreSQL-HOWTO.html
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The purpose of this document is to provide comprehensive list of pointers/URLs to quickly setup PostgreSQL and also to advocate the benefits of Open Source Code system like PostgreSQL, Linux.
Each and every computer system in the world needs a database to store/retrieve the information. The primary reason you use the computer is to store, retrieve and process information and do all these very quickly, thereby saving you time. At the same time, the system must be simple, robust, fast, reliable, economical and very easy to use. Database is the most VITAL SYSTEM as it stores mission critical information of every company in this world. Each and every industry in this world needs a database system. Industries like telecom, automobile, banks, airlines, etc.. will not function efficiently without a database system. The most popular database systems are based on the International Standard Organisation (ISO) SQL specifications and ANSI SQL (American) standards. The current specifications widely used in the industry are ISO/ANSI SQL 1992. Upcoming standard is the SQL 1998/99 which is also called SQL-3 is still under development. Popular database like Oracle, Sybase and Informix systems are based on these standards or are trying to implement these standards.
Without a standard like ANSI/ISO SQL, it would be very difficult for the customer to develop a application once and run on all the database systems. End user wants to develop an application ONCE using ISO SQL, ODBC, JDBC and deploy on all variety of database systems in the world.
The world's most popular FREE Database which implements some of the ISO SQL, ANSI SQL/98, SQL/92 and ANSI SQL/89 RDBMS is PostgreSQL. PostgreSQL is next generation Object relational database and is targeting on full compliance of SQL standards like ISO/ANSI SQL. PostgreSQL is the only free RDBMS in the world which supports Object databases and SQL. This document will tell you how-to install the database, how to set up the Web database, application database, front end GUIs and interface programs. It is strongly advised that you MUST write your database applications 100 % compliant to standards of ISO/ANSI SQL, ODBC, JDBC so that your application is portable across multiple databases like PostgreSQL, Oracle, Sybase, Informix etc.
You get the highest quality, and lot many features with PostgreSQL as it follows 'Open Source Code development model'. Open Source Code model is the one where the complete source code is given to you and the development takes place on the internet by a extremely vast network of human brains. Future trend shows that most of the software development will take place on the so called "Information Super-Highway" which spans the whole globe. In the coming years, internet growth will be explosive which will further fuel rapid adoption of PostgreSQL by the industry.
By applying the principles of statistics, mathematics and science to software quality, you get the best quality of software only in a 'Open Source Code System' like PostgreSQL, wherein the source code is open to a very vast number of human brains inter-connected by the information super-highway. Greater the number of human brains working, the better will be the quality of software. Open Source Code model will also prevent RE-INVENTION OF WHEELS, eliminates DUPLICATION OF WORK and will be very economical, saves time in distribution and follows the modern economic laws of optimizing the national and global resources. Once a software work is done by others, then you DO NOT need to re-do that again. You will not be wasting your valuable time on something which had already been WELL DONE. Your time is extremely precious and it must be utilized efficiently, because you have only 8 hours a day for doing work. As we will be entering the 21st century, there will be a change in the way that you get software for your use. Everybody will give first preference for the open source softwares like PostgreSQL, Linux.
If you buy binaries, you will not get any equity and ownership of source code. Source code is a very valuable asset and binaries have no value. Buying software may become a thing of the past. You only need to buy good hardware, it is worth spending money on the hardware and get the software from internet. Important point is that it is the computer hardware which is doing bulk of the work. Hardware is the real work horse and software is just driving it. Computer hardware is so much more complex that only 6 nations in the world so far have demonstrated the capability of designing and manufacturing computer chips/hardware. Design and manufacturing of computer chips is a advanced technology. It is a very complex process, capital intensive, requires large investments in plant and production machines which deal with 0.18 micron (even smaller than 0.18) technology. On a single small silicon chip millions of transistors/circuits are densely packed. Companies like Applied Material, AMD, Intel, Cyrix, Hitachi, IBM and others spent significant number of man-years to master the high-technology like Chip Design, Micro-electronics and Nano-electronics. Micro means (one-millionth of meter 10^-6), Nano means (one-billionth of meter 10^-9). Current technology uses micro-electronics of about 0.35 micron using aluminum as conductors and 0.25 micron sizes using copper as conductors of electrons. In near future the technology of 0.10 micron with copper and even nano-electronics will be used to make computer chips. Aluminum conductors will be phased out by copper on computer chips, as copper is a better conductor of electrons. In photolithography process extreme ultraviolet, X-ray or electron-beam techniques will be used to etch circuits for feature size less than 0.15 micron. In about 20 years from now, silicon chips will be phased out by molecular computers and bio chips which will be billions of times faster than silicon chips. Molecules are a group of atoms. And atoms are tiny particles which makes up everything that you see in this world. Molecular computers will use the molecules of matter as ultra-fast electronic on/off switches. When the switch is ON it indicates 1, and when it is OFF it indicates 0. All the computer programs in this world are based on binary (numbers 1 and 0). Table below shows the progress and future advancement trends of computer chips.
Advancement of chip capabilities in future
********************************************
+--------------------------+---------+---------+---------+---------+--------+---------+
| Item/Year | 1997 | 1999 | 2001 | 2003 | 2012 | 2020 |
+--------------------------+---------+---------+---------+---------+--------+---------+
| Feature size(micron) | 0.25 | 0.18 | 0.15 | 0.13 | 0.05 |< 0.00001|
+--------------------------+---------+---------+---------+---------+--------+---------+
| Wafer size(mm) | 200 | 300 | 300 | 300 | 450 | Mol/Bio |
+--------------------------+---------+---------+---------+---------+--------+---------+
| Min Operating Voltage | 1.8-2.5 | 1.5-1.8 | 1.2-1.5 | 1.2-1.5 | 0.5-0.6| < 0.001 |
+--------------------------+---------+---------+---------+---------+--------+---------+
| Max power dissipation | 70 | 90 | 110 | 130 | 175 | 600 |
+--------------------------+---------+---------+---------+---------+--------+---------+
| On-chip frequencey (MHz) | 750 | 1,250 | 1,500 | 2,100 | 10,000 | > 50,000|
+--------------------------+---------+---------+---------+---------+--------+---------+
| DRAM capacity | 256 MB | 1 GB | 2 GB | 4 GB | 256 GB | > 1000GB|
+--------------------------+---------+---------+---------+---------+--------+---------+
On other hand, each and every country in the world develops/makes software. In fact, any person in this world with a small low-cost PC can write software.
Databases like Oracle, Informix, Sybase, IBM DB2 (Unix) are written using the "C" language and binaries are created by compiling the source code and then they are shipped out to customers. Oracle, Sybase, Informix databases are 100 % "C" programs!!
Since a lot of work had been done on PostgreSQL for the past 14 years, it does not make sense to re-create from scratch another database system which satisfies ANSI/ISO SQL. It will be a great advantage to take the existing code and add missing features or enhancements to PostgreSQL and start using it immediately.
Prediction is that demand for "Internet products" like PostgreSQL will grow exponentially as it is capable of maintaining a high quality, low cost, extremely large user-base and developer-base. Those nations which do not use the 'Internet products' will be seriously missing "World-wide Internet Revolution" and will be left far behind other countries. The reason is "Internet" itself is the world's LARGEST "software company" and is a large software "power house"!
In this chapter, it will be shown how science plays a important role in the creation of various objects like software, this universe, mass, atoms, energy and even yourself! This chapter also shows why knowledge of science is very important before you start using the products of science.
The golden rule is - "You MUST not use a product without understanding how it is created!!" This rule applies to everything - database sytems, computer system, operating system, this universe and even your own human body! It means that you should have complete source code and information about the system. It is important to understand how human body and atoms inside human body works since humans are creating PostgreSQL, MS Windows95 etc..
Creation is a very important step. Persons who are using the objects of science must know how it is created. This applies to even computer systems and PostgreSQL. A majority of people do not have knowledge of science and hence do not know how systems like MS Windows NT/95, Oracle, human body and this universe are created. A vast majority of people do not know what made the universe and MS Windows 95/NT and what is inside it. Complex systems are built from very simple basic building blocks like - millions of universes are created, each universe in turn has millions of super-clusters, each super-cluster has millions of galaxies, each galaxy has millions of stars, some stars system have many planets, each planet in turn is made up billions of atoms.(In the history of this world, only one universe was created by a man in ancient India eons ago, but no other case had been reported in the modern history. Creating a universe is a much more advanced technology and is more advanced than the atomic bomb which was dropped on Hiroshima and Nagasaki causing horrible destruction). Modern nuclear weapons are so tiny and powerful that if such a single nuclear bomb is dropped then it can completely vaporise the planet earth! But there are also weapons which will completely NULLIFY and NEUTRALISE all the nuclear weapons in the world!! Total variety of weapons are infinity!. Software like MS Windows 95 is created simply by "C" and assembler language programs which simply uses 1 and 0 and universes like ours are created simply by dashing TWO dissimilar but proper of combination of tiny atomic particles of other dimensions. A human body is created by dashing two dissimilar but proper combination of tiny cells!! Humans inherited the properties of this universe. The universe you are currently living in was NOT there - all the atoms inside the universe was not there and not even TIME was existing!! Baby universe was born during big bang and started expanding and kept growing. Even today the universe is still expanding!! A person from another universe by name 'Brahma' created this universe you are currently living in. It is indeed possible for man to create a new universe. Total number of universes that can be created is INFINITY and similarly total number of operating systems that can be created is also infinity!! Infinite number universes and infinite variety of multi-dimensional atoms collapse down into few primary-dimensional-universe.
The laws of science and statistics favour the open-source code system like PostgreSQL and Linux. As the internet speed is increasing everyday, and internet is becoming more and MORE reliable, the open-source code system will gain very rapid momentum. And, if rules of statistics and laws of physics are correct, awareness of science grows and when IGNORANT people start learning science then the closed source-code systems will eventually vanish from this planet.
Developing a project like PostgreSQL requires resources like energy and time, hence PostgreSQL is a product of energy and time. Since energy and time can be explained only by science, there is a direct co-relation between physics and software projects like PostgreSQL, Linux. Laws of science (Physics) applies everywhere and at all the times, to anything that you do, even while you are developing the software projects.
Physics is in action even while you are talking (sound waves), walking (friction between ground and your feet), reading a book or writing software. Every science in this world has a deep root in mathematics, including PostgreSQL. PostgreSQL uses 'Modern Algebra' which is a tiny branch of mathematics. Modern algebra deals with 'Set Theory', 'Relational Algebra', science of Groups, Rings, Collections, Sets, Unions, Intersections, Exclusions, Domains, Lists, etc...
The software like PostgreSQL is existing today because of the energy and time. And mass and energy are ONE and the SAME entity. The fact that mass and energy are same was unknown to people 100 years ago! And even today it is unknown to world population that internet is the largest software "power house" and the largest "software company" in the world!
Cells in the human brains consume energy while processing (creating software), by converting the chemical energy from food into electrical and heat energy. Even while you are reading this paragraph, the cells in your brain are burning out the fuel and are using tiny amounts of energy. All of these implies that human brain is a thermodynamic heat engine. Because human brain is a thermodynamic engine, the laws of thermodynamics applies to brain and hence thermodynamics has indirect effects on software like PostgreSQL.
There can be infinite number of colors, computer langauages, computer chip designs and theories but there CANNOT be ONE SINGLE PERFECT color, computer language, design or system! What you can have is only a NEAR PERFECT color(wavelength), system, database, or theory! Nature is like a KALIEDOSCOPE - there are infinite number of dimensions, infinite variety particles of other dimensions but they all combine into very few primary dimensions and vice-versa.
By combining the energies of millions of people around the world via internet it is possible to achieve a NEAR PERFECT system (including a database software system). Individually, the energy of each person will be minute, but by networking a large number of people, the total energy will be huge which can be focused on a project to generate a near perfect system.
The energy is measured in Joules, kiloJoules or kilograms of mass, and time is measured in seconds or hours. And power is energy divided by time and is measured in Watts or kiloWatts .
Energy of each person = y Joules
or in terms of mass
Energy of each person = y grams
The conversion factor between mass and energy is E = m * c * c
where 'c' is the speed of light and 'm' is the mass.
Time = 8 hours (This is constant since each person has only 8 hours a day)
Power = Energy / Time
= (y / (8 * 60 * 60) ) Watts
Total Power of the world = n * (y / (8 * 60 * 60) ) Watts
where n = number of persons working on the project.
It is very clear that internet can network a vast number of people, which implies internet has a lot of energy and time which can produce much higher quality software products in much shorter time as compared to commercial companies. Even very big companies like Microsoft and IBM cannot overpower and overrule the laws of Physics but will eventually SURRENDER UNTO laws of science!
Conclusion is - because of laws of science, 'open source code' system like PostgreSQL, Linux will prevail and will be always much better than 'closed source code' system and it is possible to prove this statement scientifically. Man should not waste time creating too many duplicate software products.
PostgreSQL is a free database, complete source code is given to you and is a Object-Relational Database System targetting on ANSI ISO/SQL 1998, 92 and runs on diverse hardware platforms and Operating systems. The ultimate objective and the final goal of PostgreSQL is to become 100 % compliant to ANSI/ISO SQL and also to become the number ONE open generic Database in the world.
Informix Universal server (released 1997) is based on earlier version of PostgreSQL because Informix bought Illustra Inc. and integrated with Informix. Illustra database was based on Postgres (earlier version of PostgreSQL).
PostgreSQL is an enhancement of the POSTGRES database management system, a next-generation DBMS research prototype. While PostgreSQL retains the powerful data model and rich data types of POSTGRES, it replaces the PostQuel query language with an extended subset of SQL.
PostgreSQL development is being performed by a team of Internet developers who all subscribe to the PostgreSQL development mailing list. The current coordinator is Marc G. Fournier
This team is now responsible for all current and future development of PostgreSQL. Ofcourse, the database customer himself is the developer of PostgreSQL! The development load is distributed among a very large number of database end-users on internet.The authors of PostgreSQL 1.01 were Andrew Yu and Jolly Chen. Many others have contributed to the porting, testing, debugging and enhancement of the code. The original Postgres code, from which PostgreSQL is derived, was the effort of many graduate students, undergraduate students, and staff programmers working under the direction of Professor Michael Stonebraker at the University of California, Berkeley.
The original name of the software at Berkeley was Postgres. When SQL functionality was added in 1995, its name was changed to Postgres95. The name was changed at the end of 1996 to PostgreSQL.
Millions of PostgreSQL is installed as Database servers, Web database servers and Application data servers. It is very sophisticated object relational database system (ORDBMS).
PostgreSQL runs on Solaris, SunOS, HPUX, AIX, Linux, Irix, Digital Unix, BSDi,NetBSD, FreeBSD, SCO unix, NEXTSTEP, Unixware and all and every flavor of Unix. Port to Windows NT is done using Cygnus cygwin32 package.
You can buy Redhat Linux CDROM, Debian Linux CDROM or Slackware Linux CDROM which already contains the PostgreSQL in package form (both source code and binaries) from :
PostgreSQL organisation is also selling 'PostgreSQL CDROM' which contains the complete source code and binaries for many Unix operating systems as well as full documentation.
Binaries only distribution of PostgreSQL:
WWW Web sites:
The ftp sites are listed below :-
PostgreSQL source code is also available at all the mirror sites of sunsite unc (total of about 1000 sites around the globe). It is inside the Red Hat Linux distribution in /pub/contrib/i386/postgresql.rpm file.
This chapter will help you to install and run the database very quickly in less than 5 minutes.
Quick Steps to Install, Test, Verify and run PostgreSQL Login as root.
# cd /mnt/cdrom/RedHat/RPMS # man rpm # ls postgre*.rpm # rpm -qpl postgre*.rpm | less (to see list of files) # rpm -qpi postgre*.rpm (to see info of package) # cat /etc/passwd | grep postgres
# rpm -i postgre*.rpm (Must install all packages clients, devel, data
and main for pgaccess to work )
# man chkconfig
# chkconfig --add postgresql (to start pg during booting)
# /etc/rc.d/init.d/postgresql start (to start up postgres)
# man xhost
# xhost + (To give display access for pgaccess)
# su - postgres
bash$ man createdb
bash$ createdb mydatabase
bash$ man psql
bash$ psql mydatabase
..... in psql press up/down arrow keys for history line editing or \s
bash$ export DISPLAY=<hostname>:0.0
bash$ man pgaccess
bash$ pgaccess mydatabase
bash$ cd /usr/doc/postgresql*
See also "Installation Steps" from http://www.ramifordistat.net/postgres
The maintainer of PostgreSQL RPMs is Lamar Owen and is at lamar.owen@wgcr.org More details about PostgreSQL is at http://www.postgresql.org
Familiarize with RedHat RPM package manager to manage the PostgreSQL installations. Download the 'Maximum RPM' textbook from http://www.RPM.org look for the filename maximum-rpm.ps.gz And read it on linux using the gv command -
# gv maximum-rpm.ps.gz
Examples are needed to do testing of various interfaces to PostgreSQL. Install the postgresql examples directory from -
Install examples package, see Examples RPM and then do -
bash$ cd /usr/lib/pgsql/python
bash$ createdb thilo
bash$ psql thilo
thilo=> create table test (aa char(30), bb char(30) );
bash$ /usr/bin/python
>>> import _pg
>>> db = _pg.connect('thilo', 'localhost')
>>> db.query("INSERT INTO test VALUES ('ping', 'pong')")
>>> db.query("SELECT * FROM test")
eins|zwei
----+----
ping|pong
(1 row)
>>>CTRL+D
bash$
..... Seems to work - now install it properly
bash$ su - root
# cp /usr/lib/pgsql/python/_pg.so /usr/lib/python1.5/lib-dynload
Install examples package, see Examples RPM and then do -
bash$ cd /usr/doc/postgresql-6.5.3/examples/perl5 bash$ perl ./example.pl
bash$ perl -I/usr/lib/perl5/site_perl/5.005/i386-linux-thread ./example.pl
Read the example.pl file for using perl interface.
Install examples package, see Examples RPM and then do -
bash$ su root --> to change ownership of examples
# chown -R postgres /usr/doc/postgresql-6.5.3/examples
# exit
bash$ cd /usr/doc/postgresql-6.5.3/examples/libpq
bash$ gcc testlibpq.c -I/usr/include/pgsql -lpq
bash$ export PATH=$PATH:.
bash$ a.out
bash$ cd /usr/doc/postgresql-6.5.3/examples/libpq++
bash$ g++ testlibpq0.cc -I/usr/include/pgsql -I/usr/include/pgsql/libpq++
-lpq++ -lpq -lcrypt
bash$ ./a.out (Note: Ignore Error messages if you get any - as below)
> create table foo (aa int, bb char(4));
No tuples returned...
status = 1
Error returned: fe_setauthsvc: invalid name: , ignoring...
> insert into foo values ('4535', 'vasu');
No tuples returned...
status = 1
Error returned: fe_setauthsvc: invalid name: , ignoring...
> select * from foo;
aa |bb |
-----|-----|
4535 |vasu |
Query returned 1 row.
>
>CTRL+D
bash$
Install examples package, see Examples RPM and also install the following -
bash$ cd /usr/doc/postgresql-6.5.3/examples/jdbc bash$ echo $CLASSPATH --> Should show CLASSPATH=/usr/lib/jdk-x.x.x/lib/classes.zip where x.x.x is proper version numbers. bash$ export CLASSPATH=$CLASSPATH:.:/usr/lib/pgsql/jdbc6.5-1.2.jar Edit all psql.java file and comment out the 'package' line. bash$ javac psql.java bash$ java psql jdbc:postgresql:template1 postgres < password>[1] select * from pg_tables; tablename tableowner hasindexes hasrules pg_type postgres true false false pg_attribute postgres true false false [2] CTRL+C bash$
Install examples package, see Examples RPM and then do -
bash$ cd /usr/doc/postgresql-6.5.3/examples/ecpg bash$ ecpg test1.pgc -I/usr/include/pgsql bash$ cc test1.c -I/usr/include/pgsql -lecpg -lpq -lcrypt bash$ createdb mm bash$ ./a.out
Install examples package, see Examples RPM and then do -
bash$ cd /usr/doc/postgresql-6.5.3/examples/sql Under-development..
Example of Tcl/Tk interfaces is pgaccess program. Read the file /usr/bin/pgaccess using a editor -
bash$ view /usr/bin/pgaccess bash$ export DISPLAY=<hostname of your machine>:0.0 bash$ createdb mydb bash$ pgaccess mydb
Get the RPMs from http://www.mutinybaysoftware.com
To verify the top quality of PostgreSQL, run the Regression test package :- Login as root -
# rpm -i postgresql*test.rpm And see README file or install the source code tree which has regress directory # rpm -i postgresql*.src.rpm # cd /usr/src/redhat/SPECS # more postgresql*.spec (to see what system RPM packages you need to install) # rpm -bp postgresql*.spec (.. this will prep the package) Regression test needs the Makefiles and some header files like *fmgr*.h which can be built by - # rpm --short-circuit -bc postgresql*.spec ( .. use short circuit to bypass!) Abort the build by CTRL+C, when you see 'make -C common SUBSYS.o' By this time configure is successful and all makefiles and headers are created. You do not need to proceed any further # cd /usr/src/redhat/BUILD # chown -R postgres postgresql* # su - postgres bash$ cd /usr/src/redhat/BUILD/postgresql-6.5.3/src/test/regress bash$ more README bash$ make clean; make all runtest bash$ more regress.out
Sometimes emergency bug fix patches are released after the GA release of PostgreSQL. You can apply these optional patches depending upon the needs of your application. Follow these steps to apply the patches - Change directory to postgresql source directory
# rpm -i postgresql*.src.rpm
# cd /usr/src/postgresql6.5.3
# man patch
# patch -p0 < patchfile
# make clean
# make
Performance of 32-bit cpu machines will decline rapidly when the database size exceeds 5 GigaByte. You can run 30 gig database on 32-bit cpu but the performance will be degraded. Machines with 32-bit cpu imposes a limitation of 2 GB on RAM, 2 GB on file system sizes and other limitations on the operating system. Use the special filesystems for linux made by SGI, IBM or HP or ext3-fs to support file-sizes greater than 2 GB on 32-bit linux machines.
For extremely large databases, it is strongly advised to use 64-bit machines like Digital Alpha cpu, Sun Ultra-sparc 64-bit cpu, Silicon graphics 64-bit cpu, Intel Merced IA-64 cpu, HPUX 64bit machines or IBM 64-bit machines. Compile PostgreSQL under 64-bit cpu and it can support huge databases and large queries. Performance of PostgreSQL for queries on large tables and databases will be several times faster than PostgreSQL on 32-bit cpu machines. Advantage of 64-bit machines are that you get very large memory addressing space and the operating system can support very large file-systems, provide better performance with large databases, support much larger memory (RAM), have more capabilities etc..
Thanks to "Laws of Physics", it is possible to SCIENTIFICALLY verify whether PostgreSQL is working as per ISO/ANSI SQL specifications. To validate PostgreSQL, regression test package (src/test/regress) is included in the distribution. Regression test package will verify the standard SQL operations as well as the extensibility capabilities of PostgreSQL. The test package already contains hundreds of SQL test programs.
You should use the computer's high-speed power to validate the PostgreSQL, instead of using human brain power. Computers can carry out software regression tests millions or even billions of times faster than humans can. Modern computers can run billions of SQL tests in a very short time. In the near future the speed of computer will be several zillion times faster than human brain! Hence, it makes sense to use the power of computer to validate the software.
You can add more tests just in case you need to, and can upload to the primary PostgreSQL web site if you feel that it will be useful to others on internet. Regression test package helps build customer confidence and trust in PostgreSQL and facilitates rapid deployment of PostgreSQL on production systems.
Regression test package can be taken as a "VERY SOLID" technical document mutually agreed upon between the developers and end-users. PostgreSQL developers extensively use the regression test package during development period and also before releasing the software to public to ensure good quality.
Capablilities of PostgreSQL are directly reflected by the regression test package. If a functionality, syntax or feature exists in the regression test package then it is supported, and all others which are NOT listed in the package MAY not be supported by PostgreSQL!! You may need to verify those and add it to regression test package.
Web browser will be the most popular GUI front-end in the future. A major portion of code should be written in Web server scripting (and compiling) language PHP+Zend compiler, HTML, DHTML and with little bit of JavaScript and Java-Applets on web-client side. It is recommended that you migrate all of your "legacy" Windows 95/NT applications to PHP + HTML + DHTML and Zend compiler. PHP is extremely powerful as it combines the power of Perl, Java, C++, Javascript into one single language and it runs on all OSes - unixes and Windows NT/95.
The best tools in the order of preference are -
Language choices in the order of preference are -
There are other tools available - PostgreSQL has Tcl/Tk interface library in the distribution called 'pgTcl'. There is a IDE (integrated development environment) for Tcl/Tk called SpecTcl.
ODBC stands for 'Open DataBase Connectivity' established by Microsoft, is a popular standard for accessing information from various databases from different vendors. Applications written using the ODBC drivers are guaranteed to work with various databases like PostgreSQL, Oracle, Sybase, Informix etc..
UDBC is a static version of ODBC independent of driver managers and DLL support, used to embed database connectivity support directly into applications.
JDBC stands for 'Java DataBase Connectivity'. Java is a platform independent programming language developed by Sun Microsystems. Java programmers are encouraged to write database applications using the JDBC to facilitate portability across databases like PostgreSQL, Oracle, informix, etc. If you write Java applications you can get JDBC drivers for PostgreSQL from the following sites:
JDBC driver is already included in the PostgreSQL distribution in postgresql-jdbc*.rpm.
The JDBC home, guide and FAQ are located at -
Java programmers can find these for PostgreSQL very useful.
PERL is an acronym for 'Practical Extraction and Report Language'. Perl is available on each and every operating system and hardware platform in the world. You can use Perl on Windows95/NT, Apple Macintosh iMac, all flavors of Unix (Solaris, HPUX, AIX, Linux, Irix, SCO etc..), mainframe MVS, desktop OS/2, OS/400, Amdahl UTS and many others. Perl runs EVEN on many unpopular or generally-unknown operating systems and hardware!! So do not be surprised if you see perl running on a very rarely used operating system. You can imagine the vast extent of the user base and developer base of Perl.
Perl interface for PostgreSQL is included in the distribution of PostgreSQL. Check in src/pgsql_perl5 directory.
The Perl Database Interface (DBI) is a database access Application Programming Interface (API) for the Perl Language. The Perl DBI API specification defines a set of functions, variables and conventions that provide a consistent database interface independent of the actual database being used.
Get DBD-Pg-0.89.tar.gz from below
To quote Tim Bunce, the architect and author of DBI:
``DBI is a database access Application Programming Interface (API) for the Perl Language. The DBI API Specification defines a set of functions, variables and conventions that provide a consistent database interface independent of the actual database being used.''
In simple language, the DBI interface allows users to access multiple database types transparently. So, if you connecting to an Oracle, Informix, mSQL, Sybase or whatever database, you don't need to know the underlying mechanics of the 3GL layer. The API defined by DBI will work on all these database types.
A similar benefit is gained by the ability to connect to two different databases of different vendor within the one perl script, ie, I want to read data from an Oracle database and insert it back into an Informix database all within one program. The DBI layer allows you to do this simply and powerfully.
Here's a list of DBperl modules, their corresponding DBI counterparts and support information. DBI driver queries should be directed to the dbi-users mailing list.
Module Name Database Required Author DBI
----------- ----------------- ------ ---
Sybperl Sybase Michael Peppler DBD::Sybase
<mpeppler@datamig.com>
http://www.mbay.net/~mpeppler
Oraperl Oracle 6 & 7 Kevin Stock DBD::Oracle
<dbi-users@fugue.com>
Ingperl Ingres Tim Bunce & DBD::Ingres
Ted Lemon
<dbi-users@fugue.com>
Interperl Interbase Buzz Moschetti DBD::Interbase
<buzz@bear.com>
Uniperl Unify 5.0 Rick Wargo None
<rickers@coe.drexel.edu>
Pgperl Postgres Igor Metz DBD::Pg
<metz@iam.unibe.ch>
Btreeperl NDBM John Conover SDBM?
<john@johncon.com>
Ctreeperl C-Tree John Conover None
<john@johncon.com>
Cisamperl Informix C-ISAM Mathias Koerber None
<mathias@unicorn.swi.com.sg>
Duaperl X.500 Directory Eric Douglas None
User Agent
There are a few information sources on DBI.
The POD for the DBI Specification can be read with the command
$ perldoc DBI
Users of the Oraperl emulation layer bundled with DBD::Oracle, may
read up on how to program with the Oraperl interface by typing:
$ perldoc Oraperl
Users of the DBD::mSQL module may read about some of the private
functions and quirks of that driver by typing:
$ perldoc DBD::mSQL
The Frequently Asked Questions is also available as
POD documentation. Read this by typing:
$ perldoc DBI::FAQ
POD in general - Information on writing POD, and on the philosophy of POD in
general, can be read by typing:
$ perldoc perlpod
See also -
The mailing lists that users may participate in are:
If you have a core dump, try the Devel::CoreStack module for generating a stack trace from the core dump. Devel::CoreStack can be found on CPAN at:
Email the dbi-users Mailing List stack trace, module versions, perl version, test cases, operating system versions and any other pertinent information. The more information you send, the quicker developers can track problems down.
The DBI and DBD::Oracle Win32 ports are now a standard part of DBI, so, downloading DBI of version higher than 0.81 should work fine. You can access Microsoft Access and SQL-Server databases from DBI via ODBC. Supplied with DBI-0.79 (and later) is an experimental DBI 'emulation layer' for the Win32::ODBC module. It's called DBI::W32ODBC. You will need the Win32::ODBC module.
In a word, yes! DBI is hugely useful for CGI programming! In fact, CGI programming is one of two top uses for DBI.
DBI confers the ability to CGI programmers to power WWW-fronted databases to their users, which provides users with vast quantities of ordered data to play with. DBI also provides the possibility that, if a site is receiving far too much traffic than their database server can cope with, they can upgrade the database server behind the scenes with no alterations to the CGI scripts.
The Apache httpd maintains a pool of httpd children to service client requests. Using the Apache mod_perl module by Doug MacEachern, the perl interpreter is embedded with the httpd children. The CGI, DBI, and your other favorite modules can be loaded at the startup of each child. These modules will not be reloaded unless changed on disk. For more information on Apache, see the Apache Project's WWW site:
Using Edmund Mergl's Apache::DBI module, database logins are stored in a hash with each of these httpd child. If your application is based on a single database user, this connection can be started with each child. Currently, database connections cannot be shared between httpd children. Apache::DBI can be downloaded from CPAN via:
Basically, a good chance this is occurring is due to the fact that the user that you ran it from the command line as has a correctly configured set of environment variables, in the case of DBD::Oracle, variables like $ORACLE_HOME, $ORACLE_SID or TWO_TASK. The httpd process usually runs under the user id of nobody, which implies there is no configured environment. Any scripts attempting to execute in this situation will correctly fail. To solve this problem, set the environment for your database in a BEGIN ( ) block at the top of your script. This will solve the problem. Similarly, you should check your httpd error logfile for any clues, as well as the ``Idiot's Guide To Solving Perl / CGI Problems'' and ``Perl CGI Programming FAQ'' for further information. It is unlikely the problem is DBI-related. Read BOTH these documents carefully!
For some OCI example code for Oracle that has multi-threaded SELECT statements, see:
Assuming that you have created a stored procedure within the target database, eg, an Oracle database, you can use $dbh->do to immediately execute the procedure. For example,
$dbh->do( "BEGIN someProcedure END" );
Remember to perform error checking, though!
$sth = $dbh->prepare( "BEGIN foo(:1, :2, :3); END;" );
$sth->bind_param(1, $a);
$sth->bind_param_inout(2, \$path, 2000);
$sth->bind_param_inout(3, \$success, 2000);
$sth->execute;
Database creation and deletion are concepts that are entirely too abstract to be adequately supported by DBI. For example, Oracle does not support the concept of dropping a database at all! Also, in Oracle, the database server essentially is the database, whereas in mSQL, the server process runs happily without any databases created in it. The problem is too disparate to attack. Some drivers, therefore, support database creation and deletion through the private func methods. You should check the documentation for the drivers you are using to see if they support this mechanism.
NULL values in DBI are specified to be treated as the value undef. NULLs can be inserted into databases as NULL, for example:
$rv = $dbh->do( "INSERT INTO table VALUES( NULL )" );
The func method is defined within DBI as being an entry point for database-specific functionality, eg, the ability to create or drop databases. Invoking these driver-specific methods is simple, for example, to invoke a createDatabase method that has one argument, we would write:
$rv = $dbh->func( 'argument', 'createDatabase' );
PERL CLINIC : The Perl Clinic can arrange commercial support contracts for Perl, DBI, DBD::Oracle and Oraperl. Support is provided by the company with whom Tim Bunce, author of DBI, works. For more information on their services, please see :
See the section -
PgAccess is a Tcl/Tk interface to PostgreSQL. It is already included in the distribution of PostgreSQL. You may want to check out this web site for a newer copy
# man xhost # xhost + # su - postgres bash$ man pgaccess bash$ export DISPLAY=<hostname>:0.0 bash$ pgaccess mydatabase
Features of PgAccess
PgAccess windows - Main window, Table builder, Table(query) view, Visual query builder.
Tables
Queries
Sequences
Future implementation will have
INFORMATION ABOUT LIBGTCL
You will need the PostgreSQL to Tcl interface library libgtcl, lined as a Tcl/Tk 'load'-able module. The libpgtcl and the source is located in the PostgreSQL directory /src/interfaces/libpgtcl. Specifically, you will need a libpgtcl library that is 'load'-able from Tcl/Tk. This is technically different from an ordinary PostgreSQL loadable object file, because libpgtcl is a collection of object files. Under Linux, this is called libpgtcl.so. You can download from the above site a version already compiled for Linux i386 systems. Just copy libpgtcl.so into your system library director (/usr/lib). One of the solutions is to remove from the source the line containing load libpgtcl.so and to load pgaccess.tcl not with wish, but with pgwish (or wishpg) that wish that was linked with libpgtcl library.
If you get crypt not found during compilation pgaccess source tree then use -lcrypt.
MPSQL provides users with a graphical SQL interface to PostgresSQL. MPSQL is similar to Oracle's SQL Worksheet and Microsoft SQL Server's query tool WISQL. It has nice GUI and has history of commands. Also you can cut and paste and it has other nice features to improve your productivity.
ISQL is for character command line terminals. This is included in the distribution, and is called "psql". Very similar to Sybase ISQL, Oracle SQLplus. At unix prompt give command 'psql' which will put you in psql> prompt.
bash# su - postgres
bash$ man psql
bash$ psql mydatabase
Type \h to see help of commands.
MPMGR will provide a graphical management interface for PostgresSQL. You can find it at
If you do want to spend money on hardware switches than you can use VNC (Virtual Network Computing) Technology from the telecom giant AT & T. VNC is GPLed and is a free software. Using VNC you can run PostgreSQL programs on computers without monitors and display on remote boxes with monitors!! But the boxes must be connected via ethernet Network Interface Cards. VNC is at http://www.uk.research.att.com/vnc
You can stack up multiple CPU-boxes and connect to just one monitor and use the KVM (Keyboard, Video, Monitor) switch box to select the host. This saves space and avoids a lot of clutter and also eliminates monitor, keyboard and the mouse (saving anywhere from 100 to 500 US dollars per set).
Using this switch box, you can stack up many PostgreSQL servers (development, test, production), Web servers, ftp servers, Intranet servers, Mail servers, News servers in a tower shelf. The switch box can be used for controlling Windows 95/NT or OS/2 boxes as well.
Please check out these sites:
Search engine yahoo to find more companies with "Server Switches" or "KVM Switches".
It is strongly recommended to have a dedicated unix box for each PostgreSQL data-server for better performance. No other application program/processes should run on this box. See the Business section of your local newspapers for local vendors selling only intel box, 13" monochrome monitor (very low cost monitor). Local vendors sell just the hardware without any Microsoft Windows/DOS. You do not need a color monitor for the database server, as you can do remote administration from color PC workstation. Get RedHat (or some other distribution of) Linux cdrom from below -
Using KVM switch you can control many cpu boxes by just one monitor and one keyboard!
Python is becoming immensely popular "pure" object-oriented scripting language. Zope is a Web-Application server and provides interfaces to PostgreSQL. Zope is available at http://www.zope.org Python is at
AppGEN can be downloaded from
AppGEN is a high level fourth generation language and application generator for producing World Wide Web (WWW) based applications. These applications are typically used over the internet or within a corporate intranet. AppGEN applications are implemented as C scripts conforming to the Common Gateway Interface (CGI) standard supported by most Web Servers.To use AppGEN you will need the following :-
PostgresSQL, relational database management system
A CGI compatible web server such as NCSA's HTTPD
An ansi C compiler such as GCC
AppGEN consists of the following Unix (Linux) executables :-
The author, Andrew Whaley, can be contacted on
dbengine a plug 'n play Web interface for PostgreSQL created by Ingo Ciechowski. It is at
About DBENGINE : dbengine is an interface between the WWW and Postgres95 which provides simple access to any existing database within just a few minutes.PHP gives you a Perl like language in your documents, but no real Perl while AppGen and wdb-p95 require that you create some configuration file for each of your databases -- sound's like you'll first of all have to learn some sort of new meta language before you can get started.
Unlike other tools you don't have to learn any special programming or scripting language to get started with dbengine. Also there's no configuration file for each database, so you don't have to get familiar with such a new structure. However - in case you want to gain access to the full features of dbengine it'd be a good idea to know the Perl language.
The whole system can be configured by simple manipulations of an additional database that contains closer information about how to visualize your database access. You can even specify virtual Fields which are calculated on the fly right before they're displayed on the screen.
Apache is a well-known Web Server. And a module to interface PostgreSQL to Apache Webserver is at -
NeoWebScript is a programming language that allows both simple and complex programs to be embedded into HTML files.When an HTML page containing embedded NeoWebScript is requested, the NeoWebScript-enabled webserver executes the embedded script(s), producing a webpage containing customized content created by the program.
NeoWebScript is a fast, secure, easy to learn way to do powerful, server-based interactive programming directly in the HTML code in web pages. With NeoWebScript, counters, email forms, graffiti walls, guest books and visitor tracking are all easy, even for a beginning programmer. See how well NeoWebScript holds its' own vs. PERL and JavaScript.
If you'd like to install NeoWebScript on your webserver, your Webmaster needs to read our Sysop FAQ to get started. Theory of Operations will explain how NeoWebScript works, while installation will take them through the steps. Management deals with configuration issues and running the server, tests let you verify correct NeoWebScript operation, and troubleshooting deals with server problems.
There is no cost to you to use NeoWebScript-2.2 for your ISP, your intranet, or your extranet. You'll see a full license when you register to download, but it costs $ 99 if you want to embed it in your own product or use it in a commerce (eg. SSL) server.
NeoWebScript is a module for the Apache webserver that allows you to embed the Tcl/Tk programming language in your webpages as a scripting tool. It was invented by Karl Lehenbauer, NeoSoft's Chief Technical Officer, and documented, enhanced and extended by NeoSoft's programmers and technical writers.
The Apache webserver is the world's most popular webserver, accounting for 68 % of the sites polled.
Tcl/Tk is the powerful, free, cross-platform scripting language developed by Dr. John Ousterhout. In his own words
"Tcl/Tk lets software developers get the job done ten times faster than with toolkits based on C or C++. It's also a great glue language for making existing applications work together and making them more graphical and Internet-aware."
Karl Lehenbauer, Founder and Chief Technical Officer of NeoSoft, has been part of Tcl/Tk development from the very beginning. Together with Mark Diehkans, they authored Extended Tcl, also known as TclX or NeoSoft Tcl, a powerful set of extensions to the language. Many of the current core Tcl commands originated in Extended Tcl, and were then imported into the core language by Dr. Ousterhout.
NeoSoft Inc., 1770 St. James Place, Suite 500, Houston, TX 77056 USA
Tool heitml is another way to interface postgres with the world wide web. For more details contact
Helmut Emmelmann H.E.I. Informationssyteme GmbH
Wimpfenerstrasse 23 Tel. 49-621-795141
68259 Mannheim Germany Fax. 49-621-795161
heitml is a server side extension of HTML and a 4GL language at the same time. People can write web applications in the HTML style by using new HTML-like tags.
heitml (pronounced "Hi"-TML) is an extension of HTML and a full-featured 4th generation language that enables Web-based Applications to interact with data stored in SQL databases, without resorting to complex CGI scripts.
heitml extends HTML on the sever side, dynamically converting ".hei" files to HTML format and so is compatible with any web browser.It embraces the familiar, easy-to-use HTML syntax and provides a large assortment of pre-developed Tags and Libraries to take care of tasks that formerly required CGI. As XML, heitml provides user defined tags. With heitml the user defined markup can be translated to HTML and send to a browser.
heitml targets both HTML designers and professional programmers alike. HTML designers can use heitml Tags to build dynamic web pages, access SQL databases, or create complete web applications. Counters, registration databases, search forms, email forms, or hierarchical menues can all be created simply by using the pre-developed HTML-like Tags found in the many Component Libraries.
For programmers heitml embeds a complete forth generation language in HTML
(e.g. <if>, <while>, and <let> Tags),
heitml makes it possible to
- - - develop Web Sites in a structured and modular way, drastically reducing maintenance overhead.
- - - develop intelligent and interactive Web Sites, with content that dynamically adapts itself to user needs.
- - - show the content of SQL databases with no programming other than to use our library of prefined "dba" Tags.
- - - develop complex database and Catalog Shopping applications using Session Variables
heitml runs on Linux with any Web Server using the CGI interface, and is especially fast (avoiding the CGI overhead) within the APACHE Web Server using the apache API. Currently MSQL (Version 1 and 2), PostgreSQL (Version 6), mysql, and the yard databases are supported). heitml also works on Linux, BSDi, Solaris and SunOS, as well as Windows NT with CGI and ISAPI and ODBC and Windows 95.
heitml (on linux) is free for research, non-commercial and private usage. Commercial Web Sites must pay a licensing fee. The fully operational version of heitml is available for a trial period downloaded freely. (Note, however, that each ".hei" Web Page you develop will display a message identifying it as the version for non-commercial use. After registration, you will receive a key to switch off the message without having to re-install the program.)
heitml (pronounced "Hi"-TML) significantly extends and enhances the functionality of HTML by definable tags and full programming features. This makes dynamic content and database applications possible simply within the HTML world, without CGI and without external scripting or programming languages. This means you, as an HTML author, can embed applications in your web pages, simply by using some new tags without CGI and without programming. As an advanced user or programmer on the other hand you can create and program powerful tag libraries. This approach makes heitml suitable for HTML newcomers and professional programmers alike. heitml runs on the web server and dynamically generates HTML, so heitml is compatible with the internet standards and with any web browser. It allows full access to databases while shielding the user from any unneccessary CGI complexity. heitml has been developed according to the newst research and in compiler construction and transaction systems.
heitml pages are developed just the same way as HTML pages, with a text editor or HTML editor, and placed on the web server as usual. However now pages can contain dynamic heitml tags and access tag libraries. You can use these tags to access the database, to create dynamic content, to send emails, and even to create powerful applications like registration databases and shopping systems.
HTML newcomers and professional programmers alike will be amazed at how quickly and easily they can design exciting applications like our Interactive Guestbook without resorting to complex and difficult to learn CGI scripts, simply by using the tools provided in our dba Library.
heitml is accompanied by a wide range of tag libraries, to create guestbooks, database maintenance applications, extensible query forms, powerful email forms or structure your web site using a hierarchic menu. These tools are ready to go, just add the corresponding tags to your web site.
As an experienced programmer you can make fully use of the heitml persistent dynamic tuple architecture : heitml is not just a scripting language with dynamic typing, full power expression evaluation, recursive procedures and extensive parameter passing features, but it also features persistent dynamic tuples to automatically keep session data of any size.
The no-cost commercial webserver, AOLserver supports database connections to PostgreSQL for more information see
This is at
The program dbf2msql works fine with mSQL and PostgreSQL. You can find it at
This program was written by Maarten Boekhold, Faculty of Electrical Engineering TU Delft, NL Computer Architecture and Digital Technique section
You can also use a python method to read dbf files and load into a postgres database.
MDB Tools is a planned set of libraries and utilities to facilitate exporting data from MS Access databases (mdb files) into a multiuser database such as Oracle, Sybase, DB2, Informix, MySQL, Postgresql, or similar.
The "Easily Adjustable Response Program" (EARP) created by David Dougherty. EARP is a Web Database Design/Implementation tool, built on top of the PostgreSQL database system. Its functionality includes:
The main implementation of EARP is a CGI binary which runs under the http daemon to provide access to the database server. All of the design tools are built into the driver, no design takes place over anything but the web. The tools themselves require a graphical browser, the compatibility of objects designed with the tools is implementation independent, based on designing individuals preferences.
One of the main features of EARP is that it uses an Object Oriented approach to producing html pages which interface to the database. Most pages will consist of several objects. Each object is produced by some sort of tool and given a name, objects are then linked together in a callable sequence by the page tool. Objects are also reusable across multiple pages. Basic tools exist for HTML, Querys, Grabbing input from forms, Extendable Formatting of Query and Input objects, and Linking together of objects into other objects. More advanced tools include the mail tool and the multithreaded query tool.
Another feature of EARP is advanced security. Access to various areas of the EARP system can be limited in a variety of ways. To facilitate its advanced security, EARP performs checks for each connection to the system, determining what ids and groups the connecting agent belongs to. Access to areas is defined seperately, and the combination decides if access to a specific area of Earp is allowed. Moreover, all that is required to implement the security features is an http server that supports basic (or better) user authentication.
EARP is available via anonymous ftp from
WWW Interface Tool is at -
PHP also has a compiler called Zend which will vastly improve the performance. First you will write your application in PHP scripting language during development, testing and debugging. Once the project is ready for deployment you will use the Zend compiler to compile the PHP to create executable which will run very fast.Old name is Professional Home Pages (PHP) and new name is PHP Hypertext Pre-Processor
PHP is a server-side html-embedded scripting language. It lets you write simple scripts right in your .HTML files much like JavaScript does, except, unlike JavaScript PHP is not browser-dependant. JavaScript is a client-side html-embedded language while PHP is a server-side language. PHP is similar in concept to Netscape's LiveWire Pro product. If you like free fast-moving software that comes with full source code you will probably like PHP.
PHP began life as a simple little cgi wrapper written in Perl. The name of this first package was Personal Home Page Tools, which later became Personal Home Page Construction Kit.
A tool was written to easily embed SQL queries into web pages. It was basically another CGI wrapper that parsed SQL queries and made it easy to create forms and tables based on these queries. This tool was named FI (Form Interpreter).
PHP/FI version 2.0 is a complete rewrite of these two packages combined into a single program. It evolved to a simple programming language embedded inside HTML files. PHP eliminates the need for numerous small Perl cgi programs by allowing you to place simple scripts directly in your HTML files. This speeds up the overall performance of your web pages since the overhead of forking Perl several times has been eliminated. It also makes it easier to manage large web sites by placing all components of a web page in a single html file. By including support for various databases, it also makes it trivial to develop database enabled web pages. Many people find the embedded nature much easier to deal with than trying to create separate HTML and CGI files.
Now PHP/FI is renamed as PHP.
The first thing you will notice if you run a page through PHP is that it adds a footer with information about the number of times your page has been accessed (if you have compiled access logging into the binary). This is just a very small part of what PHP can do for you. It serves another very important role as a form interpreter cgi, hence the FI part of the old name. For example, if you create a form on one of your web pages, you need something to process the information on that form. Even if you just want to pass the information to another web page, you will have to have a cgi program do this for you. PHP makes it extremely easy to take form data and do things with it.
Suppose you have a form:
<FORM ACTION="/cgi-bin/php.cgi/~userid/display.html" METHOD=POST>
<INPUT TYPE="text" name="name">
<INPUT TYPE="text" name="age">
<INPUT TYPE="submit">
<FORM>
< ?echo "Hi $ name, you are $ age years old!<p>" >
The next step once you have figured out how to use variables is to start playing with some logical flow tags in your pages. For example, if you wanted to display different messages based on something the user inputs, you would use if/else logic. In our above example, we can display different things based on the age the user entered by changing our display.html to:
<?
if($age>50);
echo "Hi $name, you are ancient!<p>";
elseif($age>30);
echo "Hi $name, you are very old!<p>";
else;
echo "Hi $name.";
endif;
>
You can also use PHP to configure who is allowed to access your pages. This is done using a built-in configuration screen. With this you could for example specify that only people from certain domains would be allowed to see your pages, or you could create a rule which would password protect certain pages. See the Access Control section for more details.
PHP is also capable of receiving file uploads from any RFC-1867 compliant web browser. This feature lets people upload both text and binary files. With PHP's access control and logical functions, you have full control over who is allowed to upload and what is to be done with the file once it has been uploaded. See the File Upload section for more details.
PHP has support for the PostgreSQL database package. It supports embedded SQL queries in your .HTML files.
PHP also has support for the mysql database package. It supports embedded SQL queries in your .HTML files.
A good way to run PHP is by using a cgi redirection module with the Apache server. Please note that you do not need to worry about redirection modules if you are using the Apache module version of PHP. There are two of these redirection modules available. One is developed by Dave Andersen
and it is available at and the other comes bundled with Apache and is called mod_actions.c. The modules are extremely similar. They differ slightly in their usage. Both have been tested and both work with PHP.Check the Apache documentation on how to add a module. Generally you add the module name to a file called Configuration. The line to be added if you want to use the mod_actions module is:
Module action_module mod_actions.o
If you are using the mod_cgi_redirect.c module add this line:
Module cgi_redirect_module mod_cgi_redirect.o
Then compile your httpd and install it. To configure the cgi redirection you need to either create a new mime type in your mime.types file or you can use the AddType command in your srm.conf file to add the mime type. The mime type to be added should be something like this:
application/x-httpd-php phtml
Action application/x-httpd-php /cgi-bin/php.cgi
CgiRedirect application/x-httpd-php /cgi-bin/php.cgi
Once you have one of these cgi redirection modules installed and configured correctly, you will be able to specify that you want a file parsed by PHP simply by making the file's extension .phtml. Furthermore, if you add index.phtml to your DirectoryIndex configuration line in your srm.conf file then the top-level page in a directory will be automatically parsed by php if your index file is called index.phtml.
You can automatically redirect requests for files with a given extension to be handled by PHP by using the Netscape Server CGI Redirection module. This module is available in the File Archives on the PHP Home Page. The README in the package explicitly explains how to configure it for use with PHP.
NCSA does not currently support modules, so in order to do cgi redirection with this server you need to modify your server source code. A patch to do this with NCSA 1.5 is available in the PHP file archives.
If you build the CGI version of PHP, you can use it from the command line simply typing: php.cgi filename where filename is the file you want to parse. You can also create standalone PHP scripts by making the first line of your script look something like:
#!/usr/local/bin/php.cgi -q
Python in an interpreted, object orientated scripting language. It is simple to use (light syntax, simple and straighforward statements), and has many extensions for building GUIs, interfacing with WWW, etc. An intelligent web browser (HotJava like) is currently under development (november 1995), and this should open programmers many doors. Python is copyrighted by Stichting S Mathematisch Centrum, Amsterdam, The Netherlands, and is freely distributable. It contains support for dynamic loading of objects, classes, modules, and exceptions. Adding interfaces to new system libraries through C code is straightforward, making Python easy to use in custom settings. Python is a very high level scripting language with X interface. Python package is distributed on Linux cdroms includes most of the standard Python modules, along with modules for interfacing to the Tix widget set for Tk.
PyGreSQL is a python module that interfaces to a PostgreSQL database. It embeds the PostgreSQL query library to allow easy use of the powerful PostgreSQL features from a Python script. PyGreSQL is written by D'Arcy J.M. Cain and Pascal Andre.
The home sites of the differents packages are:
If you need information about these packages please check their web sites:
For support :
See the section -
WDB-P95 - A Web interface to PostgreSQL Databases was created by J. Douglas Dunlop It is at
You can try out CASI Tape and Image Query. You can have a peek at the Form Definition File (FDF) which is used to create the CASI Tape and Image Query too, which includes a JOIN of 2 tables.
This release contains all files necessary to install and run WDB-P95 as an interface to your PostgreSQL databases. To port this system to other database should be relatively easy - provided that it supports standard SQL and has a Perl interface.
No - the PostgreSQL server does not have to be on the same host. As WDB-P95 is called by the http daemon, they have to be on the same host. - And as WDB-P95 was written to use Pg.pm - pgperl has to be on the same host too. Pgperl was written using the libpq library, so it will be able to access any PostgreSQL server anywhere in the net, just like any other PostgreSQL client. As illustrated below
(WWW Client (Netscape)) => (HTTP Server (NCSA's http) + WDB-P95 + pgperl + libpq)=> (PostgreSQL server)
Curly brackets () represent machines.
Each machine can be of a different type : NT, SUN, HP, ... but you need the libpq interface library for the machine type where you plan to use WDB-P95, as you need it to compile pgperl. (The system was designed to use HTML tables so a recent WWW client is best)
It is included in distribution and is called 'libpq'. Similar to Oracle OCI, Sybase DB-lib, Informix CLI libraries.
It is included in distribution and is called 'libpq++'. See the section - Testing C and C++ PostgreSQL interface
ESQL/C 'Embedded C Pre-compiler' for PostgreSQL ESQL/C is like Oracle Pro*C, Informix ESQL/C. The PostgreSQL ESQL/C is an SQL application-programming interface (API) enables the C programmer to create custom applications with database-management capabilities. The PostgreSQL ESQL/C allows you to use a third-generation language with which you are familiar and still take advantage of the Structured Query Language (SQL).
ESQL/C consists of the following pieces of software:
Bitwise operators was written by Nicolas Moldavsky
"C" functions that implement bitwise operators (AND, OR, XOR, bit complement) on pgsql. Get them by anonymous FTP from Makefile for Linux is included.It is at the following site
Port to Windows NT is done and is available from http://www.postgresql.org. You can download the PostgreSQL binaries for Windows NT from download page and will save you time. If you want to re-compile the source tree then follow the instructions given below. Porting to NT is done using Cygnus cygwin32 package which has gcc, gmake for Win NT/95.
The authors of Windows NT port of PostgreSQL are -
You don't have /bin would you like to mount cygwin as /bin?" [ y/n ] Select 'n', and the other options are selected 'y'
cp /cygwin32_ipc-1.03/bin/* c:/usr/local/bin cp /cygwin32_ipc-1.03/include/sys/* c:/usr/local/include/sys cp /cygwin32_ipc-1.03/lib/* c:/usr/local/lib cp c:/usr/local/bin/* /bin cp c:/Unix/Root/cygwin-b20/H-i586-cygwin32/bin/* /bin
mount c:/usr/local/include /usr/local/include mount c:/usr/local/lib /usr/local/lib cp /local/lib/* /usr/local/lib
mkdir -p c:/Postgres/{Source,Binary}
mkdir c:/Postgres/Binary/pgsql
mkdir -p /usr/src/pgsql
mkdir -p /usr/local/pgsql
mount -b c:/Postgres/Binary/pgsql /usr/local/pgsql mount c:/Postgres/Source/pgsql /usr/src/pgsql mount c:/Unix/Root/cygwin-b20/share /sw/cygwin-b20/share
cp un.h c:/Unix/Root/cygwin-b20/H-i586-cygwin32/i586-cygwin32/include/sys cp endian.h c:/Unix/Root/cygwin-b20/H-i586-cygwin32/i586-cygwin32/include cp tcp.h c:/Unix/Root/cygwin-b20/H-i586-cygwin32/i586-cygwin32/include/netinet
PATH=$PATH:/usr/local/pgsql/bin:/usr/local/bin PGDATA=/usr/local/pgsql/data PGLIB=/usr/local/pgsql/lib LD_LIBRARY_PATH=/usr/local/pgsql/lib:/usr/local/lib export LD_LIBRARY_PATH PATH PGDATA PGLIB
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Now there is an "unofficial" list of postgreSQL in Spanish. To subscribe the user has to send a message to:
The body of the message should contain the single line:inscripcion pgsql-ayuda
The following are included in the PostgreSQL distribution in the postscript, HTML formats and unix man-pages. They are located in /usr/doc/postgresql* directory. If you have access to internet, you can find the documents listed below at http://www.postgresql.org/docs
Is a a part of PSQL command
There is a script in the /tools directory in source code tree.
Use the command psql \h
Look at the regression tests at src/test. There you can find the directories
regress/sql and suite/*.sql and also see <ref id="Examples RPM">
SQL tutorial scripts is in the directory src/tutorial
Morgan Kaufman Publisher is one of best SQL books. This deals with SQL92.
Addison-Wesley Publishing company is also a good book. Very popular book for SQL.
Stephen Cannan and Gerard Otten
McGraw-Hill Book Company Europe , Berkshire, SL6 2QL, England
Martin Gruber, Technical Editor: Joe Celko
SYBEX Inc. 2021 Challenger Drive Alameda, CA 94501
This book is the Bible of Database Management Systems.
The book details normalization, SQL, recovery, concurrency, security,
integrity, and extensions to the original relational model, current issues
like client/server systems and the Object Oriented model(s). Many
references are included for further reading. Recommended for most users.
Book details theory of relational databases, relational algebra, calculus
and normalisation. But it does not cover real world issues and examples
beyond simple examples. Recommended for most users.
Recommended for most users.
This book is a collection of papers that have been published over the
years on databases. It's not for the casual user but it is really a
reference for advanced (post-graduate) students or database system
developers.
This book is a collection of papers that have been published over the
years on databases. It's not for the casual user but it is really a
reference for advanced (post-graduate) students or database system
developers.
This book goes into the details of access methods, storage techniques.
It's not for the casual user but it is for advanced (post-graduate)
students or database system developers.
Wrox Press Ltd.
Unit 16, 20 James Road, Tyseley
Birmingham, B11 2BA, England
1995
Technology
QED and John Wiley
1991
Presents the requirements of building client/server database
applications via repository metamodels and the use of ANSI standard SQL
1993
Hundreds of other titles on SQL are available! Check out a bookstore.
ANSI/ISO SQL specifications documents can be found at these sites listed below -
See Appendix A of this document Appendix A
The SQL 1998 (SQL 3) specification is still under development. See 'Electronic Access to the SQL3 Working Draft' of this document at SQL 1998
See Appendix B of this document Appendix B
This directory contains the language specification for a temporal extension to the SQL-92 language standard. This new language is designated TSQL2.
The language specification present here is the final version of the language.
Correspondence may be directed to the chair of the TSQL2 Language Design Committee, Richard T.Snodgrass, Department of Computer Science, University of Arizona, Tucson, AZ 85721,
The affiliations and e-mail addresses of the TSQL2 Language Design Committee members may be found in a separate section at the end of the language specification.The contents of this directory are as follows.
spec.dvi,.ps TSQL2 Language Specification, published in September, 1994
bookspec.ps TSQL2 Language Specification, as it appears in the TSQL2 book, published in September, 1995 (see below).
sql3 change proposals submitted to the ANSI and ISO SQL3 committees.
Associated with the language specification is a collection of commentaries which discuss design decisions, provide examples, and consider how the language may be implemented. These commentaries were originally proposals to the TSQL2 Language Design Committee. They now serve a different purpose: to provide examples of the constructs, motivate the many decisions made during the language design, and compare TSQL2 with the many other language proposals that have been made over the last fifteen years. It should be emphasized that these commentaries are not part of the TSQL2 language specification per se, but rather supplement and elaborate upon it. The language specification proper is the final word on TSQL2.
The commentaries, along with the language specification, several indexes, and other supporting material, has been published as a book:
Snodgrass, R.T., editor, The TSQL2 Temporal Query Language, Kluwer Academic Publishers, 1995, 674+xxiv pages.
The evaluation commentary appears in the book in an abbreviated form; the full commentary is provided in this directory as file eval.ps
The file tl2tsql2.pl is a prolog program that tranlates allowed temporal logic to TSQL2. This program was written by Michael Boehlen
He may be contacted for a paper that describes this translation. This is a rather dated version of that program. Newer versions are available at (the TimeDB and Tiger systems).This document shows you how to (legally) acquire a copy of the SQL-92 standard and how to acquire a copy of the "current" SQL3 Working Draft.
The standard is copyrighted ANSI standard by ANSI, the ISO standard by ISO.
There are two (2) current SQL standards, an ANSI publication and an ISO publication. The two standards are word-for-word identical except for such trivial matters as the title of the document, page headers, the phrase "International Standard" vs "American Standard", and so forth.
Buying the SQL-92 Standard
The ISO standard, ISO/IEC 9075:1992, Information Technology - Database Languages - SQL, is currently (March, 1993) available and in stock from ANSI at:
American National Standards Institute
1430 Broadway
New York, NY 10018 (USA)
Phone (sales): +1.212.642.4900
If you purchase either document from ANSI, it will have a handling charge of 7% added to it (that is, about US$9.10). Overseas shipping charges will undoubtedly add still more cost. ANSI requires a hardcopy of a company purchase order to accompany all orders; alternately, you can send a check drawn on a US bank in US dollars, which they will cash and clear before shipping your order. (An exception exists: If your organization is a corporate member of ANSI, then ANSI will ship the documents and simply bill your company.)
The ISO standard is also available outside the United States from local national bodies (country standardization bodies) that are members of either ISO (International Organization for Standardization) or IEC (International Electrotechnical Commission). Copies of the list of national bodies and their addresses are available from ANSI or from other national bodies. They are also available from ISO:
International Organization for Standardization
Central Secretariat
1, rue de Varembi
CH-1211 Genhve 20
Switzerland
Global Engineering Documents
2805 McGaw Ave
Irvine, CA 92714 (USA)
USA
Phone (works from anywhere): +1.714.261.1455
Phone (only in the USA): (800)854-7179
Buying a copy of the SQL3 Working Draft
You can purchase a hardcopy of the SQL3 working draft from the ANSI X3 Secretariat, CBEMA (Computer and Business Equipment Manufacturers Association). They intend to keep the "most recent" versions of the SQL3 working draft available and sell them for about US$60.00 to US$65.00. You can contact CBEMA at:
CBEMA, X3 Secretariat
Attn: Lynn Barra
1250 Eye St.
Suite 200
Washington, DC 20005 (USA)
Electronic Access to the SQL3 Working Draft
The most recent version (as of the date of this writing) of the SQL3 (both ANSI and ISO) working draft (and all of its Parts) is available by "anonymous ftp" or by "ftpmail" on:
gatekeeper.dec.com
at
/pub/standards/sql/
In general, you can find files with names like:
sql-bindings-mar94.ps
sql-bindings-mar94.txt
sql-cli-mar94.ps
sql-cli-mar94.txt
sql-foundation-mar94.ps
sql-foundation-mar94.txt
sql-framework-mar94.ps
sql-framework-mar94.txt
sql-psm-mar94.ps
sql-psm-mar94.txt
In addition, for those readers unable to get a directory listing by FTP, we have placed a file with the name:
ls
Retrieving Files Directly Using ftp
This is a sample of how to use FTP. Specifically, it shows how to connect to gatekeeper.dec.com, get to the directory where the base document is kept, and transfer the document to your host. Note that your host must have Internet access to do this. The login is 'ftp' and the password is your email address (this is sometimes referred to as 'anonymous ftp'). The command 'type binary' is used to ensure that no bits are stripped from the file(s) received. 'get' gets one file at a time. Comments in the script below are inside angle brackets < like so > .
% ftp gatekeeper.dec.com
Connected to gatekeeper.dec.com.
220- *** /etc/motd.ftp ***
Gatekeeper.DEC.COM is an unsupported service of DEC Corporate Research.
<...this goes on for a while...>
220 gatekeeper.dec.com FTP server (Version 5.83 Sat ... 1992) ready.
Name (gatekeeper.dec.com:<yourlogin here>): ftp <anonymous also works>
331 Guest login ok, send ident as password.
Password: <enter your email address here >
230 Guest login ok, access restrictions apply.
Remote system type is UNIX. <or whatever>
Using binary mode to transfer files.
ftp> cd pub/standards/sql
250 CWD command successful.
ftp> dir
200 PORT command successful.
150 Opening ASCII mode data connection for /bin/ls.
total 9529
-r--r--r-- 1 root system 357782 Feb 25 10:18 x3h2-93-081.ps
-r--r--r-- 1 root system 158782 Feb 25 10:19 x3h2-93-081.txt
-r--r--r-- 1 root system 195202 Feb 25 10:20 x3h2-93-082.ps
-r--r--r-- 1 root system 90900 Feb 25 10:20 x3h2-93-082.txt
-r--r--r-- 1 root system 5856284 Feb 25 09:55 x3h2-93-091.ps
-r--r--r-- 1 root system 3043687 Feb 25 09:57 x3h2-93-091.txt
226 Transfer complete.
ftp> type binary
200 Type set to I.
ftp> get x3h2-93-082.txt
200 PORT command successful.
150 Opening BINARY mode data connection for x3h2-93-082.txt (90900 bytes).
226 Transfer complete.
90900 bytes received in 0.53 seconds (166.11 Kbytes/s)
ftp> quit
% <the file is now in your directory as x3h2-93-082.txt>
Digital Equipment Corporation, like several other companies, provides ftp email service. The response can take several days, but it does provide a service equivalent to ftp for those without direct Internet ftp access. The address of the server is:
ftpmail@decwrl.dec.com
The following script will retrieve the PostScript for the latest version of the SQL3 document:
reply joe.programmer@imaginary-corp.com
connect gatekeeper.dec.com anonymous
binary
compress
reply joe.programmer@imaginary-corp.com
connect gatekeeper.dec.com anonymous
binary
compress
uuencode
chdir /pub/standards/sql
get x3h2-93-091.ps
quit
reply joe.programmer@imaginary-corp.com
connect gatekeeper.dec.com anonymous
chdir /pub/standards/sql
get x3h2-93-091.ps
quit
To retrieve any particular file, other than x3h2-93-091.ps, simply replace "x3h2-93-091.ps" with the name of the desired file. To get a directory listing of all files available, replace "get x3h2-93-091.ps" with "dir".
This chapter is a source of information about the SQL standards process and its current state.
Current Status:
Development is currently underway to enhance SQL into a computationally complete language for the definition and management of persistent, complex objects. This includes: generalization and specialization hierarchies, multiple inheritance, user defined data types, triggers and assertions, support for knowledge based systems, recursive query expressions, and additional data administration tools. It also includes the specification of abstract data types (ADTs), object identifiers, methods, inheritance, polymorphism, encapsulation, and all of the other facilities normally associated with object data management.
In the fall of 1996, several parts of SQL3 went through a ISO CD ballot. Those parts were SQL/Framework, SQL/Foundation, and SQL/Bindings. Those ballots failed (as expected) with 900 or so comments. In Late January, there was an ISO DBL editing meeting that processed a large number of problem solutions that were either included with ballot comments or submitted as separate papers. Since the DBL editing meeting was unable to process all of the comments, the editing meeting has been extended. The completion of the editing meeting is scheduled for the end of July, 1997, in London.
Following the July editing meeting, the expectation is that a Final CD ballot will be requested for these parts of SQL. The Final CD process will take about 6 months and a DBL editing meeting, after which there will be a DIS ballot and a fairly quick IS ballot.
The ISO procedures have changed since SQL/92, so the SQL committees are still working through the exact details of the process.
If everything goes well, these parts of SQL3 will become an official ISO/IEC standard in late 1998, but the schedule is very tight.
In 1993, the ANSI and ISO development committees decided to split future SQL development into a multi-part standard. The Parts are:
In the USA, the entirety of SQL3 is being processed as both an ANSI Domestic ("D") project and as an ISO project. The expected time frame for completion of SQL3 is currently 1999.
The SQL/CLI and SQL/PSM are being processed as fast as possible as addendums to SQL-92. In the USA, these are being processed only as International ("I") projects. SQL/CLI was completed in 1995. SQL/PSM should be completed sometime in late 1996.
In addition to the SQL3 work, a number of additional projects are being persued:
Standards Committee and Process
There are actually a number of SQL standards committees around the world. There is an international SQL standards group as a part of ISO. A number of countries have committees that focus on SQL. These countries (usually) send representatives to ISO/IEC JTC1/SC 21/WG3 DBL meetings. The countries that actively participate in the ISO SQL standards process are:
NIST Validation
SQL implementations are validated (in the Unites States) by the National Institute of Standards and Training (NIST). NIST currently has a validation test suite for entry level SQL-92. The exact details of the NIST validation requirements are defined as a Federal Information Processing Standard (FIPS). The current requirements for SQL are defined in FIPS 127-2. The Postscript and Text versions of this document can be retrieved from NIST. The current SQL Validated Products List can also be retrieved from NIST.
Standard SQL Publications and Articles
There are two versions of the SQL standard. Both are available from ANSI:
The two versions of the SQL standard are identical except for the front matter and references to other standards. Both versions are available from:
American National Standards Institute
1430 Broadway
New York, NY 10018
USA
Phone (sales): +1.212.642.4900
* Technical Corrigendum 1:1994 to ISO/IEC 9075:1992
In addition to the standards, several books have been written about the 1992 SQL standard. These books provide a much more readable description of the standard than the actual standard.
Related Standards
A number of other standards are of interest to the SQL community. This section contains pointers to information on those efforts. These pointers will be augmented as additional information becomes available on the web.
A significant portion of the SQL3 effort is in the SQL Foundation document:
There are several prerequisites to the object oriented capabilities:
These capabilities are defined as a part of SQL/PSM
A great deal of work is currently being done to refine the SQL-3 object model and align it with the object model proposed by ODMG. This effort is described in the X3H2 and ISO DBL paper: Accomodating SQL3 and ODMG. A recent update on the SQL3/OQL Merger is also available.
SQL3 Timing
Work on SQL3 is well underway, but the final standards is several years away.
The ANSI version of the standard will be on a similar schedule.
The SQL/CLI is a programing call level interface to SQL databases. It is designed to support database access from shrink-wrapped applications. The CLI was originally created by a subcommittee of the SQL Access Group (SAG). The SAG/CLI specification was published as the Microsoft Open DataBase Connectivity (ODBC) specification in 1992. In 1993, SAG submitted the CLI to the ANSI and ISO SQL committees. (The SQL Access Group has now merged with X/Open consortium.)
SQL/CLI provides an international standard for:
SQL/CLI Timing
For the standards process, SQL/CLI is being processed with blinding speed.
SQL/PSM expands SQL by adding:
In addition to being a valuable application development tool, SQL/PSM provides the foundation support for the object oriented capabilities in SQL3.
Multi-statement and Stored Procedures
Multi-statement and stored procedures offer a variety of advantages in a client/server environment:
Procedural Language Extensions
Procedural language add the power of a traditional programming language to SQL through flow control statements and a variety of other programming constructs.
Flow Control Statements
The procedural language extensions include other programming language constructs:
In addition, all of the traditional SQL statements can be included in multi-statement procedures.
External Procedure and Function Calls
One feature frequently mentioned in the wish lists for many database products, and implemented in some, is a capability augmenting the built-in features with calls to user-written procedures external to the database software.
The benefit of this capability is that it gives the database (and therefore database applications) access to a rich set of procedures and functions too numerous to be defined by a standards committee.
SQL/PSM Timing
SQL/PSM is proceeding quickly:
For ease of reference, the programming language bindings have been pulled out into a separate document. The current version is simply an extract of the dynamic and embedded bindings from SQL-92.
A variety of issues remain unresolved for the programming language bindings.
For traditional programming language, mappings exist for the SQL-92 datatypes. However, mappings must be defined between SQL objects and programming language variables.
For object oriented languages, mapping must be defined for the current SQL datatypes and between the SQL object model and the object model of the object-oriented language.
The object model needs to stabilize before these can be addressed.
The language bindings will be completed as a part of SQL3.
This specification would standardize an application program interface (API) between a global Transaction Manager and an SQL Resource Manager. It would standardize the function calls, based upon the semantics of ISO/IEC 10026, "Distributed Transaction Processing", that an SQL Resource Manager would have to support for two-phase commit. The base document is derived from an X/Open publication, with X/Open permission, that specifies explicit input and output parameters and semantics, in terms of SQL data types, for the following functions: xa_close, xa_commit, xa_complete, xa_end, xa_forget, xa_open, xa_prepare, xa_recover, xa_rollback, and xa_start.
ISO is currently attempting to fast-track the X/Open XA specification. The fast-track process adopts a current industry specification with no changes. The XA fast-track ballot at the ISO SC21, JTC 1 level started on April 27, 1995 and ends on October 27, 1995. If the XA specification is approved by 75% of the votes, and by 2/3 of the p-members of JTC 1, it will become an International Standard. If the fast-track ballot is approved, SQL/XA could become a standard in 1996.
Temporal SQL deals with time-related data. The concept is that it is useful to query data to discover what it looked like at a particular point in time. Temporal SQL is a December, 1994 paper by Rick Snodgrass describing the concepts.
X3 Announces the Approval of a New Project, ISO/IEC 9075 Part 7: SQL/Temporal is a press release related to SQL/Temporal.
----------------------------------------------------------------------------
Temporal SQL
************
Rick Snodgrass (chair of the TSQL2 committee)
31-Dec-1994
Valid-time support goes beyond that of a temporal ADT. With the later, a column is specified as of a temporal domain, such as DATE or INTERVAL (examples will be given shortly). With valid time, the rows of a table vary over time, as reality changes. The timestamp associated with a row of a valid-time table is interpreted by the query language as the time when the combination of values of the columns in the row was valid. This implicit timestamp allows queries to be expressed succinctly and intuitively.
The University of Arizona's Office of Appointed Personnel has some information in a database, including each employee's name, their current salary, and their current title. This can be represented by a simple table.
Employee(Name, Salary, Title)
SELECT Salary
FROM Employee
WHERE Name = 'Bob'
Employee(Name, Salary, Title, DateofBirth DATE)
SELECT DateofBirth
FROM Employee
WHERE Name = 'Bob'
The OAP wishes to computerize the employment history. To do so, they append two columns, one indicating when the information in the row became valid, the other indicating when the information was no longer valid.
Employee (Name, Salary, Title, DateofBirth, Start DATE, Stop DATE)
To the data model, these new columns are identical to DateofBirth. However, their presence has wide-ranging consequences.
To find an employee's current salary, things are more difficult.
SELECT Salary
FROM Employee
WHERE Name = 'Bob' AND Start <= CURRENT_DATE AND CURRENT_DATE <= Stop
Name Salary Title DateofBirth Start Stop
---- ------ ----- ----------- ----- ----
Bob 60000 Assistant Provost 1945-04-09 1993-01-01 1993-05-30
Bob 70000 Assistant Provost 1945-04-09 1993-06-01 1993-09-30
Bob 70000 Provost 1945-04-09 1993-10-01 1994-01-31
Bob 70000 Professor 1945-04-09 1994-02-01 1994-12-31
Figure 1
Name Salary Start Stop
---- ------ ----- ----
Bob 60000 1993-01-01 1993-05-30
Bob 70000 1993-06-01 1994-12-31
CREATE TABLE Temp(Salary, Start, Stop)
AS SELECT Salary, Start, Stop
FROM Employee;
UPDATE Temp T1
SET (T1.Stop) = (SELECT MAX(T2.Stop)
FROM Temp AS T2
WHERE T1.Salary = T2.Salary AND T1.Start < T2.Start
AND T1.Stop >= T2.Start AND T1.Stop < T2.Stop)
WHERE EXISTS (SELECT *
FROM Temp AS T2
WHERE T1.Salary = T2.Salary AND T1.Start < T2.Start
AND T1.Stop >= T2.Start AND T1.Stop < T2.Stop)
until no rows updated;
DELETE FROM Temp T1
WHERE EXISTS (SELECT *
FROM Temp AS T2
WHERE T1.Salary = T2.Salary
AND ((T1.Start > T2.Start AND T1.Stop <= T2.Stop)
OR (T1.Start >= T2.Start AND T1.Stop < T2.Stop))
A third alternative is to use SQL only to open a cursor on the table. A linked list of periods is maintained, each with a salary. This linked list should be initialized to empty.
DECLARE emp_cursor CURSOR FOR
SELECT Salary, Title, Start, Stop
FROM Employee;
OPEN emp_cursor;
loop:
FETCH emp_cursor INTO :salary, :start, :stop;
if no-data returned then goto finished;
find position in linked list to insert this information;
goto loop;
finished:
CLOSE emp_cursor;
The linked list may not be necessary in this case if the cursor is ORDER BY Start.
In any case, the query, a natural one, is quite difficult to express using the facilities present in SQL-92. The query is trivial in TSQL2.
SELECT Salary
FROM Employee
A more drastic approach is to avoid the problem of extracting the salary history by reorganizing the schema to separate salary, title, and date of birth information (in the following, we ignore the date of birth, for simplicity).
Employee1 (Name, Salary, Start DATE, Stop DATE)
Employee2 (Name, Title, Start DATE, Stop DATE)
Name Salary Start Stop
---- ------ ----- ----
Bob 60000 1993-01-01 1993-05-30
Bob 70000 1993-06-01 1993-12-31
Name Title Start Stop
---- ------ ----- ----
Bob Assistant Provost 1993-01-01 1993-09-30
Bob Provost 1993-10-01 1994-01-31
Bob Professor 1994-02-01 1994-12-31
SELECT Salary, Start, Stop
FROM Employee1
WHERE Name = 'Bob'
SELECT Employee1.Name, Salary, Dept, Employee1.Start, Employee1.Stop
FROM Employee1, Employee2
WHERE Employee1.Name = Employee2.Name
AND Employee2.Start <= Employee1.Start AND Employee1.Stop < Employee2.Stop
UNION
SELECT Employee1.Name, Salary, Dept, Employee1.Start, Employee2.Stop
FROM Employee1, Employee2
WHERE Employee1.Name = Employee2.Name
AND Employee1.Start >= Employee2.Start AND Employee2.Stop < Employee1.Stop
AND Employee1.Start < Employee2.Stop
UNION
SELECT Employee1.Name, Salary, Dept, Employee2.Start, Employee1.Stop
FROM Employee1, Employee2
WHERE Employee1.Name = Employee2.Name
AND Employee2.Start > Employee1.Start AND Employee1.Stop < Employee2.Stop
AND Employee2.Start < Employee1.Stop
UNION
SELECT Employee1.Name, Salary, Dept, Employee2.Start, Employee2.Stop
FROM Employee1, Employee2
WHERE Employee1.Name = Employee2.Name
AND Employee2.Start > Employee1.Start AND Employee2.Stop < Employee1.Stop
SELECT Employee1.Name, Salary, Dept
FROM Employee1, Employee2
WHERE Employee1.Name = Employee2.Name
Now the OAP is asked, what is the maximum salary? Before adding time, this was easy.
SELECT MAX(Salary)
FROM Employee
SELECT Salary
FROM Employee AS E1
WHERE NOT EXISTS (SELECT *
FROM Employee AS E2
WHERE E2.Salary > E1.Salary)
CREATE TABLE Temp (Salary, Start, Stop)
AS SELECT Salary, Start, Stop
FROM Employee;
INSERT INTO Temp
SELECT T.Salary, T.Start, E.Start
FROM Temp AS T, Employee AS E
WHERE E.Start >= T.Start AND E.Start < T.Stop AND E.Salary > T.Salary;
INSERT INTO Temp
SELECT T.Salary, T.Stop, E.Stop
FROM Temp AS T, Employee AS E
WHERE E.Stop > T.Start AND E.Stop <= T.Stop AND E.Salary > T.Salary;
DELETE FROM Temp T
WHERE EXISTS (SELECT *
FROM Employee AS E
WHERE ((T.Start => E.Start AND T.Start < E.Stop)
OR (E.Start >= T.Start AND E.Start < T.Stop))
AND E.Salary > T.Salary;
A third alternative is to use SQL as little as possible, and instead compute the desired maximum history in a host language using cursors.
The query in TSQL2 is again straightforward and intuitive.
SELECT MAX(Salary)
FROM Employee
Time-varying data is manipulated in most database applications. Valid-time support is absent in SQL. Many common temporal queries are either difficult to simulate in SQL, or require embedding SQL in a procedural language, due to SQL's lack of support for valid-time tables in its data model and query constructs.
Elsewhere, we showed that adding valid-time support requires few changes to the DBMS implementation, can dramatically simplify some queries and enable others, and can later enable optimizations in storage structures, indexing methods, and optimization strategies that can yield significant performance improvements.
With a new part of SQL3 supporting time-varying information, we can begin to address such applications, enabling SQL3 to better manage temporal data.
----------------------------------------------------------------------------
Accredited Standards Committee* X3, Information Technology
NEWS RELEASE
Doc. No.: PR/96-0002
Reply to: Barbara Bennett at bbennett@itic.nw.dc.us
X3 Announces the Approval of a New Project, ISO/IEC
9075 Part 7: SQL/Temporal
Washington D.C., January 1996
----------------------------------------------------------------------------
Inquiries regarding this project should be sent to the
Chairman of X3H2,
Dr. Donald R. Deutsch,
Sybase, Inc., Suite 800,
6550 Rock Spring
Drive, Bethesda, MD 20817.
Email: deutsch@sybase.com.
X3 Secretariat at
1250 Eye Street
NW, Suite 200,
Washington DC 20005.
Email: x3sec@itic.nw.dc.us
FAX: (202)638-4922.
A new ISO/IEC international standardization project for development of an SQL class library for multimedia applications was approved in early 1993. This new standardization activity, named SQL Multimedia (SQL/MM), will specify packages of SQL abstract data type (ADT) definitions using the facilities for ADT specification and invocation provided in the emerging SQL3 specification. SQL/MM intends to standardize class libraries for science and engineering, full-text and document processing, and methods for the management of multimedia objects such as image, sound, animation, music, and video. It will likely provide an SQL language binding for multimedia objects defined by other JTC1 standardization bodies (e.g. SC18 for documents, SC24 for images, and SC29 for photographs and motion pictures).
The Project Plan for SQL/MM indicates that it will be a multi-part standard consisting of an evolving number of parts. Part 1 will be a Framework that specifies how the other parts are to be constructed. Each of the other parts will be devoted to a specific SQL application package. The following SQL/MM Part structure exists as of August 1994:
There are a number of standards efforts in the area of Spatial and Geographic information:
If you have any technical question or encounter any problem you can e-mail to:
Also PostgreSQL organisation is selling technical support to companies, the revenue generated will be used for maintaining several mirror sites (web and ftp) around the world. The revenue will also be used to produce printed documentation, guides, textbooks which will help the customers.
You can also take help from professional consulting firms like RedHat, Anderson, WGS (Work Group Solutions). Contact them for help, since they have very good expertise in "C", "C++" (PostgreSQL is written in "C") -
Commercial databases pay many taxes like federal, state, sales, employment, social security, medicare taxes, health care for employees, bunch of benefits for employees, marketing and advertisement costs. All these costs do not go directly for the development of the database and do not improve the quality or technology of the database. When you buy a commercial database, some portion of the amount goes for overheads like taxes, expenses and balance for database R&D costs.
Also commercial databases have to pay for buildings/real-estates and purchase Unix machines, install and maintain them. All of these costs are passed onto customers.
PostgreSQL has the advantage over commercial databases as there is no direct taxes since it is made on the internet. A very vast group of people contribute to the development of the PostgreSQL. For example, in a hypothetical case, if there are one million companies in U.S.A and each contribute about $ 10 (worth of software to PostgreSQL) then each and every company will get ten million dollars!! This is the GREAT MAGIC of software development on internet.
Currently, PostgreSQL source code is about 2,50,000 lines of "C", "C++" code. If cost of each line of "C" code is $ 2 then the PostgreSQL is worth about $ 5,00,000 (half a million dollars!).
Many companies already develop in-house vast amount of "C", "C++" code. Hence by taking in the source code of PostgreSQL and collaborating with other companies on internet will greatly benefit the company saving time and efforts.
Listed below are other SQL databases for Unix, Linux.
Internet is very vast and it has vast number of software and has a ocean of information underneath. It is growing at the rate of 300% annually world wide. It is estimated that there are about 10 million Web sites world wide!
To search for a information you would use search engines like "Yahoo", "Netscape", "Lycos" etc. Go to Yahoo, click on search. Use filtering options to narrow down your search criteria. The default search action is "Intelligent search" which is more general and lists all possiblities. Click on "Options" to select "EXACT phrase" search, "AND" search, "OR" search, etc.. This way you would find the information you need much faster. Also in the search menu, there are radio-buttons for searching in Usenet, Web-sites and Yahoo sites.
After researching all the available databases which are free and source code is available, it was found that ONLY PostgreSQL is the MOST mature, most widely used and robust RDBMS SQL free database (object relational) in the world.
PostgreSQL is very appealing since lot of work had already been done. It has ODBC and JDBC drivers, using these it is possible to write applications independent of the databases. The applications written in PostgreSQL using ODBC, JDBC drivers are easily portable to other databases like Oracle, Sybase and Informix and vice versa.
You may ask "But why PostgreSQL ?" The answer is, since it takes lot more time to develop a database system from scratch, it makes sense to pick up a database system which satisfies the following conditions -
A database system
Please refer to the latest version of FAQ for General, Linux and Irix at
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man xdvi
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ghostscript howto.ps
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This file contains a depth-first tree traversal of the BNF
for the language done at about 27-AUG-1992 11:03:41.64.
The specific version of the BNF included here is: ANSI-only, SQL2-only.
<SQL terminal character> ::=
<SQL language character>
| <SQL embedded language character>
<SQL language character> ::=
<simple Latin letter>
| <digit>
| <SQL special character>
<simple Latin letter> ::=
<simple Latin upper case letter>
| <simple Latin lower case letter>
<simple Latin upper case letter> ::=
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O
| P | Q | R | S | T | U | V | W | X | Y | Z
<simple Latin lower case letter> ::=
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o
| p | q | r | s | t | u | v | w | x | y | z
<digit> ::=
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
<SQL special character> ::=
<space>
| <double quote>
| <percent>
| <ampersand>
| <quote>
| <left paren>
| <right paren>
| <asterisk>
| <plus sign>
| <comma>
| <minus sign>
| <period>
| <solidus>
| <colon>
| <semicolon>
| <less than operator>
| <equals operator>
| <greater than operator>
| <question mark>
| <underscore>
| <vertical bar>
<space> ::= !! <EMPHASIS>(space character in character set in use)
<double quote> ::= "
<percent> ::= %
<ampersand> ::= &
<quote> ::= '
<left paren> ::= (
<right paren> ::= )
<asterisk> ::= *
<plus sign> ::= +
<comma> ::= ,
<minus sign> ::= -
<period> ::= .
<solidus> ::= /
<colon> ::= :
<semicolon> ::= ;
<less than operator> ::= <
<equals operator> ::= =
<greater than operator> ::= >
<question mark> ::= ?
<underscore> ::= _
<vertical bar> ::= |
<SQL embedded language character> ::=
<left bracket>
| <right bracket>
<left bracket> ::= [
<right bracket> ::= ]
<token> ::=
<nondelimiter token>
| <delimiter token>
<nondelimiter token> ::=
<regular identifier>
| <key word>
| <unsigned numeric literal>
| <national character string literal>
| <bit string literal>
| <hex string literal>
<regular identifier> ::= <identifier body>
<identifier body> ::=
<identifier start> [ ( <underscore> | <identifier part> )... ]
<identifier start> ::= <EMPHASIS>(!! See the Syntax Rules)
<identifier part> ::=
<identifier start>
| <digit>
<key word> ::=
<reserved word>
| <non-reserved word>
<reserved word> ::=
ABSOLUTE | ACTION | ADD | ALL
| ALLOCATE | ALTER | AND
| ANY | ARE
| AS | ASC
| ASSERTION | AT
| AUTHORIZATION | AVG
| BEGIN | BETWEEN | BIT | BIT_LENGTH
| BOTH | BY
| CASCADE | CASCADED | CASE | CAST
| CATALOG
| CHAR | CHARACTER | CHAR_LENGTH
| CHARACTER_LENGTH | CHECK | CLOSE | COALESCE
| COLLATE | COLLATION
| COLUMN | COMMIT
| CONNECT
| CONNECTION | CONSTRAINT
| CONSTRAINTS | CONTINUE
| CONVERT | CORRESPONDING | COUNT | CREATE | CROSS
| CURRENT
| CURRENT_DATE | CURRENT_TIME
| CURRENT_TIMESTAMP | CURRENT_USER | CURSOR
| DATE | DAY | DEALLOCATE | DEC
| DECIMAL | DECLARE | DEFAULT | DEFERRABLE
| DEFERRED | DELETE | DESC | DESCRIBE | DESCRIPTOR
| DIAGNOSTICS
| DISCONNECT | DISTINCT | DOMAIN | DOUBLE | DROP
| ELSE | END | END-EXEC | ESCAPE
| EXCEPT | EXCEPTION
| EXEC | EXECUTE | EXISTS
| EXTERNAL | EXTRACT
| FALSE | FETCH | FIRST | FLOAT | FOR
| FOREIGN | FOUND | FROM | FULL
| GET | GLOBAL | GO | GOTO
| GRANT | GROUP
| HAVING | HOUR
| IDENTITY | IMMEDIATE | IN | INDICATOR
| INITIALLY | INNER | INPUT
| INSENSITIVE | INSERT | INT | INTEGER | INTERSECT
| INTERVAL | INTO | IS
| ISOLATION
| JOIN
| KEY
| LANGUAGE | LAST | LEADING | LEFT
| LEVEL | LIKE | LOCAL | LOWER
| MATCH | MAX | MIN | MINUTE | MODULE
| MONTH
| NAMES | NATIONAL | NATURAL | NCHAR | NEXT | NO
| NOT | NULL
| NULLIF | NUMERIC
| OCTET_LENGTH | OF
| ON | ONLY | OPEN | OPTION | OR
| ORDER | OUTER
| OUTPUT | OVERLAPS
| PAD | PARTIAL | POSITION | PRECISION | PREPARE
| PRESERVE | PRIMARY
| PRIOR | PRIVILEGES | PROCEDURE | PUBLIC
| READ | REAL | REFERENCES | RELATIVE | RESTRICT
| REVOKE | RIGHT
| ROLLBACK | ROWS
| SCHEMA | SCROLL | SECOND | SECTION
| SELECT
| SESSION | SESSION_USER | SET
| SIZE | SMALLINT | SOME | SPACE | SQL | SQLCODE
| SQLERROR | SQLSTATE
| SUBSTRING | SUM | SYSTEM_USER
| TABLE | TEMPORARY
| THEN | TIME | TIMESTAMP
| TIMEZONE_HOUR | TIMEZONE_MINUTE
| TO | TRAILING | TRANSACTION
| TRANSLATE | TRANSLATION | TRIM | TRUE
| UNION | UNIQUE | UNKNOWN | UPDATE | UPPER | USAGE
| USER | USING
| VALUE | VALUES | VARCHAR | VARYING | VIEW
| WHEN | WHENEVER | WHERE | WITH | WORK | WRITE
| YEAR
| ZONE
<non-reserved word> ::=
ADA
| C | CATALOG_NAME
| CHARACTER_SET_CATALOG | CHARACTER_SET_NAME
| CHARACTER_SET_SCHEMA | CLASS_ORIGIN | COBOL | COLLATION_CATALOG
| COLLATION_NAME | COLLATION_SCHEMA | COLUMN_NAME | COMMAND_FUNCTION
| COMMITTED
| CONDITION_NUMBER | CONNECTION_NAME | CONSTRAINT_CATALOG | CONSTRAINT_NAME
| CONSTRAINT_SCHEMA | CURSOR_NAME
| DATA | DATETIME_INTERVAL_CODE
| DATETIME_INTERVAL_PRECISION | DYNAMIC_FUNCTION
| FORTRAN
| LENGTH
| MESSAGE_LENGTH | MESSAGE_OCTET_LENGTH | MESSAGE_TEXT | MORE | MUMPS
| NAME | NULLABLE | NUMBER
| PASCAL | PLI
| REPEATABLE | RETURNED_LENGTH | RETURNED_OCTET_LENGTH | RETURNED_SQLSTATE
| ROW_COUNT
| SCALE | SCHEMA_NAME | SERIALIZABLE | SERVER_NAME | SUBCLASS_ORIGIN
| TABLE_NAME | TYPE
| UNCOMMITTED | UNNAMED
<unsigned numeric literal> ::=
<exact numeric literal>
| <approximate numeric literal>
<exact numeric literal> ::=
<unsigned integer> [ <period> [ <unsigned integer> ] ]
| <period> <unsigned integer>
<unsigned integer> ::= <digit>...
<approximate numeric literal> ::= <mantissa> E <exponent>
<mantissa> ::= <exact numeric literal>
<exponent> ::= <signed integer>
<signed integer> ::= [ <sign> ] <unsigned integer>
<sign> ::= <plus sign> | <minus sign>
<national character string literal> ::=
N <quote> [ <character representation>... ] <quote>
[ ( <separator>... <quote> [ <character representation>... ] <quote> )... ]
<character representation> ::=
<nonquote character>
| <quote symbol>
<nonquote character> ::= !! <EMPHASIS>(See the Syntax Rules.)
<quote symbol> ::= <quote><quote>
<separator> ::= ( <comment> | <space> | <newline> )...
<comment> ::=
<comment introducer> [ <comment character>... ] <newline>
<comment introducer> ::= <minus sign><minus sign>[<minus sign>...]
<comment character> ::=
<nonquote character>
| <quote>
<newline> ::= !! <EMPHASIS>(implementation-defined end-of-line indicator)
<bit string literal> ::=
B <quote> [ <bit>... ] <quote>
[ ( <separator>... <quote> [ <bit>... ] <quote> )... ]
<bit> ::= 0 | 1
<hex string literal> ::=
X <quote> [ <hexit>... ] <quote>
[ ( <separator>... <quote> [ <hexit>... ] <quote> )... ]
<hexit> ::= <digit> | A | B | C | D | E | F | a | b | c | d | e | f
<delimiter token> ::=
<character string literal>
| <date string>
| <time string>
| <timestamp string>
| <interval string>
| <delimited identifier>
| <SQL special character>
| <not equals operator>
| <greater than or equals operator>
| <less than or equals operator>
| <concatenation operator>
| <double period>
| <left bracket>
| <right bracket>
<character string literal> ::=
[ <introducer><character set specification> ]
<quote> [ <character representation>... ] <quote>
[ ( <separator>... <quote> [ <character representation>... ] <quote> )... ]
<introducer> ::= <underscore>
<character set specification> ::=
<standard character repertoire name>
| <implementation-defined character repertoire name>
| <user-defined character repertoire name>
| <standard universal character form-of-use name>
| <implementation-defined universal character form-of-use name>
<standard character repertoire name> ::= <character set name>
<character set name> ::= [ <schema name> <period> ]
<SQL language identifier>
<schema name> ::=
[ <catalog name> <period> ] <unqualified schema name>
<catalog name> ::= <identifier>
<identifier> ::=
[ <introducer><character set specification> ] <actual identifier>
<actual identifier> ::=
<regular identifier>
| <delimited identifier>
<delimited identifier> ::=
<double quote> <delimited identifier body> <double quote>
<delimited identifier body> ::= <delimited identifier part>...
<delimited identifier part> ::=
<nondoublequote character>
| <doublequote symbol>
<nondoublequote character> ::= <EMPHASIS>(!! See the Syntax Rules)
<doublequote symbol> ::= <double quote><double quote>
<unqualified schema name> ::= <identifier>
<SQL language identifier> ::=
<SQL language identifier start>
[ ( <underscore> | <SQL language identifier part> )... ]
<SQL language identifier start> ::= <simple Latin letter>
<SQL language identifier part> ::=
<simple Latin letter>
| <digit>
<implementation-defined character repertoire name> ::=
<character set name>
<user-defined character repertoire name> ::= <character set name>
<standard universal character form-of-use name> ::=
<character set name>
<implementation-defined universal character form-of-use name> ::=
<character set name>
<date string> ::=
<quote> <date value> <quote>
<date value> ::=
<years value> <minus sign> <months value>
<minus sign> <days value>
<years value> ::= <datetime value>
<datetime value> ::= <unsigned integer>
<months value> ::= <datetime value>
<days value> ::= <datetime value>
<time string> ::=
<quote> <time value> [ <time zone interval> ] <quote>
<time value> ::=
<hours value> <colon> <minutes value> <colon> <seconds value>
<hours value> ::= <datetime value>
<minutes value> ::= <datetime value>
<seconds value> ::=
<seconds integer value> [ <period> [ <seconds fraction> ] ]
<seconds integer value> ::= <unsigned integer>
<seconds fraction> ::= <unsigned integer>
<time zone interval> ::=
<sign> <hours value> <colon> <minutes value>
<timestamp string> ::=
<quote> <date value> <space> <time value>
[ <time zone interval> ] <quote>
<interval string> ::=
<quote> ( <year-month literal> | <day-time literal> ) <quote>
<year-month literal> ::=
<years value>
| [ <years value> <minus sign> ] <months value>
<day-time literal> ::=
<day-time interval>
| <time interval>
<day-time interval> ::=
<days value>
[ <space> <hours value> [ <colon> <minutes value>
[ <colon> <seconds value> ] ] ]
<time interval> ::=
<hours value> [ <colon> <minutes value> [ <colon> <seconds value> ] ]
| <minutes value> [ <colon> <seconds value> ]
| <seconds value>
<not equals operator> ::= <>
<greater than or equals operator> ::= >=
<less than or equals operator> ::= <=
<concatenation operator> ::= ||
<double period> ::= ..
<module> ::=
<module name clause>
<language clause>
<module authorization clause>
[ <temporary table declaration>... ]
<module contents>...
<module name clause> ::=
MODULE [ <module name> ]
[ <module character set specification> ]
<module name> ::= <identifier>
<module character set specification> ::=
NAMES ARE <character set specification>
<language clause> ::=
LANGUAGE <language name>
<language name> ::=
ADA | C | COBOL | FORTRAN | MUMPS | PASCAL | PLI
<module authorization clause> ::=
SCHEMA <schema name>
| AUTHORIZATION <module authorization identifier>
| SCHEMA <schema name>
AUTHORIZATION <module authorization identifier>
<module authorization identifier> ::=
<authorization identifier>
<authorization identifier> ::= <identifier>
<temporary table declaration> ::=
DECLARE LOCAL TEMPORARY TABLE
<qualified local table name>
<table element list>
[ ON COMMIT ( PRESERVE | DELETE ) ROWS ]
<qualified local table name> ::=
MODULE <period> <local table name>
<local table name> ::= <qualified identifier>
<qualified identifier> ::= <identifier>
<table element list> ::=
<left paren> <table element> [ ( <comma> <table element> )... ] <right paren>
<table element> ::=
<column definition>
| <table constraint definition>
<column definition> ::=
<column name> ( <data type> | <domain name> )
[ <default clause> ]
[ <column constraint definition>... ]
[ <collate clause> ]
<column name> ::= <identifier>
<data type> ::=
<character string type>
[ CHARACTER SET <character set specification> ]
| <national character string type>
| <bit string type>
| <numeric type>
| <datetime type>
| <interval type>
<character string type> ::=
CHARACTER [ <left paren> <length> <right paren> ]
| CHAR [ <left paren> <length> <right paren> ]
| CHARACTER VARYING <left paren> <length> <right paren>
| CHAR VARYING <left paren> <length> <right paren>
| VARCHAR <left paren> <length> <right paren>
<length> ::= <unsigned integer>
<national character string type> ::=
NATIONAL CHARACTER [ <left paren> <length> <right paren> ]
| NATIONAL CHAR [ <left paren> <length> <right paren> ]
| NCHAR [ <left paren> <length> <right paren> ]
| NATIONAL CHARACTER VARYING <left paren> <length> <right paren>
| NATIONAL CHAR VARYING <left paren> <length> <right paren>
| NCHAR VARYING <left paren> <length> <right paren>
<bit string type> ::=
BIT [ <left paren> <length> <right paren> ]
| BIT VARYING <left paren> <length> <right paren>
<numeric type> ::=
<exact numeric type>
| <approximate numeric type>
<exact numeric type> ::=
NUMERIC [ <left paren> <precision> [ <comma> <scale> ] <right paren> ]
| DECIMAL [ <left paren> <precision> [ <comma> <scale> ] <right paren> ]
| DEC [ <left paren> <precision> [ <comma> <scale> ] <right paren> ]
| INTEGER
| INT
| SMALLINT
<precision> ::= <unsigned integer>
<scale> ::= <unsigned integer>
<approximate numeric type> ::=
FLOAT [ <left paren> <precision> <right paren> ]
| REAL
| DOUBLE PRECISION
<datetime type> ::=
DATE
| TIME [ <left paren> <time precision> <right paren> ]
[ WITH TIME ZONE ]
| TIMESTAMP [ <left paren> <timestamp precision> <right paren> ]
[ WITH TIME ZONE ]
<time precision> ::= <time fractional seconds precision>
<time fractional seconds precision> ::= <unsigned integer>
<timestamp precision> ::= <time fractional seconds precision>
<interval type> ::= INTERVAL <interval qualifier>
<interval qualifier> ::=
<start field> TO <end field>
| <single datetime field>
<start field> ::=
<non-second datetime field>
[ <left paren> <interval leading field precision> <right paren> ]
<non-second datetime field> ::= YEAR | MONTH | DAY | HOUR
| MINUTE
<interval leading field precision> ::= <unsigned integer>
<end field> ::=
<non-second datetime field>
| SECOND [ <left paren> <interval fractional seconds precision> <right paren> ]
<interval fractional seconds precision> ::= <unsigned integer>
<single datetime field> ::=
<non-second datetime field>
[ <left paren> <interval leading field precision> <right paren> ]
| SECOND [ <left paren> <interval leading field precision>
[ <comma> <interval fractional seconds precision> ] <right paren> ]
<domain name> ::= <qualified name>
<qualified name> ::=
[ <schema name> <period> ] <qualified identifier>
<default clause> ::=
DEFAULT <default option>
<default option> ::=
<literal>
| <datetime value function>
| USER
| CURRENT_USER
| SESSION_USER
| SYSTEM_USER
| NULL
<literal> ::=
<signed numeric literal>
| <general literal>
<signed numeric literal> ::=
[ <sign> ] <unsigned numeric literal>
<general literal> ::=
<character string literal>
| <national character string literal>
| <bit string literal>
| <hex string literal>
| <datetime literal>
| <interval literal>
<datetime literal> ::=
<date literal>
| <time literal>
| <timestamp literal>
<date literal> ::=
DATE <date string>
<time literal> ::=
TIME <time string>
<timestamp literal> ::=
TIMESTAMP <timestamp string>
<interval literal> ::=
INTERVAL [ <sign> ] <interval string> <interval qualifier>
<datetime value function> ::=
<current date value function>
| <current time value function>
| <current timestamp value function>
<current date value function> ::= CURRENT_DATE
<current time value function> ::=
CURRENT_TIME [ <left paren> <time precision> <right paren> ]
<current timestamp value function> ::=
CURRENT_TIMESTAMP [ <left paren> <timestamp precision> <right paren> ]
<column constraint definition> ::=
[ <constraint name definition> ]
<column constraint>
[ <constraint attributes> ]
<constraint name definition> ::= CONSTRAINT <constraint name>
<constraint name> ::= <qualified name>
<column constraint> ::=
NOT NULL
| <unique specification>
| <references specification>
| <check constraint definition>
<unique specification> ::=
UNIQUE | PRIMARY KEY
<references specification> ::=
REFERENCES <referenced table and columns>
[ MATCH <match type> ]
[ <referential triggered action> ]
<referenced table and columns> ::=
<table name> [ <left paren> <reference column list> <right paren> ]
<table name> ::=
<qualified name>
| <qualified local table name>
<reference column list> ::= <column name list>
<column name list> ::=
<column name> [ ( <comma> <column name> )... ]
<match type> ::=
FULL
| PARTIAL
<referential triggered action> ::=
<update rule> [ <delete rule> ]
| <delete rule> [ <update rule> ]
<update rule> ::= ON UPDATE <referential action>
<referential action> ::=
CASCADE
| SET NULL
| SET DEFAULT
| NO ACTION
<delete rule> ::= ON DELETE <referential action>
<check constraint definition> ::=
CHECK
<left paren> <search condition> <right paren>
<search condition> ::=
<boolean term>
| <search condition> OR <boolean term>
<boolean term> ::=
<boolean factor>
| <boolean term> AND <boolean factor>
<boolean factor> ::=
[ NOT ] <boolean test>
<boolean test> ::=
<boolean primary> [ IS [ NOT ]
<truth value> ]
<boolean primary> ::=
<predicate>
| <left paren> <search condition> <right paren>
<predicate> ::=
<comparison predicate>
| <between predicate>
| <in predicate>
| <like predicate>
| <null predicate>
| <quantified comparison predicate>
| <exists predicate>
| <unique predicate>
| <match predicate>
| <overlaps predicate>
<comparison predicate> ::=
<row value constructor> <comp op>
<row value constructor>
<row value constructor> ::=
<row value constructor element>
| <left paren> <row value constructor list> <right paren>
| <row subquery>
<row value constructor element> ::=
<value expression>
| <null specification>
| <default specification>
<value expression> ::=
<numeric value expression>
| <string value expression>
| <datetime value expression>
| <interval value expression>
<numeric value expression> ::=
<term>
| <numeric value expression> <plus sign> <term>
| <numeric value expression> <minus sign> <term>
<term> ::=
<factor>
| <term> <asterisk> <factor>
| <term> <solidus> <factor>
<factor> ::=
[ <sign> ] <numeric primary>
<numeric primary> ::=
<value expression primary>
| <numeric value function>
<value expression primary> ::=
<unsigned value specification>
| <column reference>
| <set function specification>
| <scalar subquery>
| <case expression>
| <left paren> <value expression> <right paren>
| <cast specification>
<unsigned value specification> ::=
<unsigned literal>
| <general value specification>
<unsigned literal> ::=
<unsigned numeric literal>
| <general literal>
<general value specification> ::=
<parameter specification>
| <dynamic parameter specification>
| <variable specification>
| USER
| CURRENT_USER
| SESSION_USER
| SYSTEM_USER
| VALUE
<parameter specification> ::=
<parameter name> [ <indicator parameter> ]
<parameter name> ::= <colon> <identifier>
<indicator parameter> ::=
[ INDICATOR ] <parameter name>
<dynamic parameter specification> ::= <question mark>
<variable specification> ::=
<embedded variable name> [ <indicator variable> ]
<embedded variable name> ::=
<colon><host identifier>
<host identifier> ::=
<Ada host identifier>
| <C host identifier>
| <COBOL host identifier>
| <Fortran host identifier>
| <MUMPS host identifier>
| <Pascal host identifier>
| <PL/I host identifier>
<Ada host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<C host identifier> ::=
!! <EMPHASIS>(See the Syntax Rules.)
<COBOL host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<Fortran host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<MUMPS host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<Pascal host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<PL/I host identifier> ::= !! <EMPHASIS>(See the Syntax Rules.)
<indicator variable> ::=
[ INDICATOR ] <embedded variable name>
<column reference> ::= [ <qualifier> <period> ] <column name>
<qualifier> ::=
<table name>
| <correlation name>
<correlation name> ::= <identifier>
<set function specification> ::=
COUNT <left paren> <asterisk> <right paren>
| <general set function>
<general set function> ::=
<set function type>
<left paren> [ <set quantifier> ] <value expression> <right paren>
<set function type> ::=
AVG | MAX | MIN | SUM | COUNT
<set quantifier> ::= DISTINCT | ALL
<scalar subquery> ::= <subquery>
<subquery> ::= <left paren> <query expression> <right paren>
<query expression> ::=
<non-join query expression>
| <joined table>
<non-join query expression> ::=
<non-join query term>
| <query expression> UNION [ ALL ]
[ <corresponding spec> ] <query term>
| <query expression> EXCEPT [ ALL ]
[ <corresponding spec> ] <query term>
<non-join query term> ::=
<non-join query primary>
| <query term> INTERSECT [ ALL ]
[ <corresponding spec> ] <query primary>
<non-join query primary> ::=
<simple table>
| <left paren> <non-join query expression> <right paren>
<simple table> ::=
<query specification>
| <table value constructor>
| <explicit table>
<query specification> ::=
SELECT [ <set quantifier> ] <select list> <table expression>
<select list> ::=
<asterisk>
| <select sublist> [ ( <comma> <select sublist> )... ]
<select sublist> ::=
<derived column>
| <qualifier> <period> <asterisk>
<derived column> ::= <value expression> [ <as clause> ]
<as clause> ::= [ AS ] <column name>
<table expression> ::=
<from clause>
[ <where clause> ]
[ <group by clause> ]
[ <having clause> ]
<from clause> ::= FROM <table reference>
[ ( <comma> <table reference> )... ]
<table reference> ::=
<table name> [ [ AS ] <correlation name>
[ <left paren> <derived column list> <right paren> ] ]
| <derived table> [ AS ] <correlation name>
[ <left paren> <derived column list> <right paren> ]
| <joined table>
<derived column list> ::= <column name list>
<derived table> ::= <table subquery>
<table subquery> ::= <subquery>
<joined table> ::=
<cross join>
| <qualified join>
| <left paren> <joined table> <right paren>
<cross join> ::=
<table reference> CROSS JOIN <table reference>
<qualified join> ::=
<table reference> [ NATURAL ] [ <join type> ] JOIN
<table reference> [ <join specification> ]
<join type> ::=
INNER
| <outer join type> [ OUTER ]
| UNION
<outer join type> ::=
LEFT
| RIGHT
| FULL
<join specification> ::=
<join condition>
| <named columns join>
<join condition> ::= ON <search condition>
<named columns join> ::=
USING <left paren> <join column list> <right paren>
<join column list> ::= <column name list>
<where clause> ::= WHERE <search condition>
<group by clause> ::=
GROUP BY <grouping column reference list>
<grouping column reference list> ::=
<grouping column reference>
[ ( <comma> <grouping column reference> )... ]
<grouping column reference> ::=
<column reference> [ <collate clause> ]
<collate clause> ::= COLLATE <collation name>
<collation name> ::= <qualified name>
<having clause> ::= HAVING <search condition>
<table value constructor> ::=
VALUES <table value constructor list>
<table value constructor list> ::=
<row value constructor> [ ( <comma> <row value constructor> )... ]
<explicit table> ::= TABLE <table name>
<query term> ::=
<non-join query term>
| <joined table>
<corresponding spec> ::=
CORRESPONDING [ BY <left paren> <corresponding column list> <right paren> ]
<corresponding column list> ::= <column name list>
<query primary> ::=
<non-join query primary>
| <joined table>
<case expression> ::=
<case abbreviation>
| <case specification>
<case abbreviation> ::=
NULLIF <left paren> <value expression> <comma>
<value expression> <right paren>
| COALESCE <left paren> <value expression>
( <comma> <value expression> )... <right paren>
<case specification> ::=
<simple case>
| <searched case>
<simple case> ::=
CASE <case operand>
<simple when clause>...
[ <else clause> ]
END
<case operand> ::= <value expression>
<simple when clause> ::= WHEN <when operand> THEN <result>
<when operand> ::= <value expression>
<result> ::= <result expression> | NULL
<result expression> ::= <value expression>
<else clause> ::= ELSE <result>
<searched case> ::=
CASE
<searched when clause>...
[ <else clause> ]
END
<searched when clause> ::= WHEN <search condition> THEN <result>
<cast specification> ::=
CAST <left paren> <cast operand> AS
<cast target> <right paren>
<cast operand> ::=
<value expression>
| NULL
<cast target> ::=
<domain name>
| <data type>
<numeric value function> ::=
<position expression>
| <extract expression>
| <length expression>
<position expression> ::=
POSITION <left paren> <character value expression>
IN <character value expression> <right paren>
<character value expression> ::=
<concatenation>
| <character factor>
<concatenation> ::=
<character value expression> <concatenation operator>
<character factor>
<character factor> ::=
<character primary> [ <collate clause> ]
<character primary> ::=
<value expression primary>
| <string value function>
<string value function> ::=
<character value function>
| <bit value function>
<character value function> ::=
<character substring function>
| <fold>
| <form-of-use conversion>
| <character translation>
| <trim function>
<character substring function> ::=
SUBSTRING <left paren> <character value expression> FROM <start position>
[ FOR <string length> ] <right paren>
<start position> ::= <numeric value expression>
<string length> ::= <numeric value expression>
<fold> ::= ( UPPER | LOWER )
<left paren> <character value expression> <right paren>
<form-of-use conversion> ::=
CONVERT <left paren> <character value expression>
USING <form-of-use conversion name> <right paren>
<form-of-use conversion name> ::= <qualified name>
<character translation> ::=
TRANSLATE <left paren> <character value expression>
USING <translation name> <right paren>
<translation name> ::= <qualified name>
<trim function> ::=
TRIM <left paren> <trim operands> <right paren>
<trim operands> ::=
[ [ <trim specification> ] [ <trim character> ] FROM ] <trim source>
<trim specification> ::=
LEADING
| TRAILING
| BOTH
<trim character> ::= <character value expression>
<trim source> ::= <character value expression>
<bit value function> ::=
<bit substring function>
<bit substring function> ::=
SUBSTRING <left paren> <bit value expression> FROM <start position>
[ FOR <string length> ] <right paren>
<bit value expression> ::=
<bit concatenation>
| <bit factor>
<bit concatenation> ::=
<bit value expression> <concatenation operator> <bit factor>
<bit factor> ::= <bit primary>
<bit primary> ::=
<value expression primary>
| <string value function>
<extract expression> ::=
EXTRACT <left paren> <extract field>
FROM <extract source> <right paren>
<extract field> ::=
<datetime field>
| <time zone field>
<datetime field> ::=
<non-second datetime field>
| SECOND
<time zone field> ::=
TIMEZONE_HOUR
| TIMEZONE_MINUTE
<extract source> ::=
<datetime value expression>
| <interval value expression>
<datetime value expression> ::=
<datetime term>
| <interval value expression> <plus sign> <datetime term>
| <datetime value expression> <plus sign> <interval term>
| <datetime value expression> <minus sign> <interval term>
<interval term> ::=
<interval factor>
| <interval term 2> <asterisk> <factor>
| <interval term 2> <solidus> <factor>
| <term> <asterisk> <interval factor>
<interval factor> ::=
[ <sign> ] <interval primary>
<interval primary> ::=
<value expression primary> [ <interval qualifier> ]
<interval term 2> ::= <interval term>
<interval value expression> ::=
<interval term>
| <interval value expression 1> <plus sign> <interval term 1>
| <interval value expression 1> <minus sign> <interval term 1>
| <left paren> <datetime value expression> <minus sign>
<datetime term> <right paren> <interval qualifier>
<interval value expression 1> ::= <interval value expression>
<interval term 1> ::= <interval term>
<datetime term> ::=
<datetime factor>
<datetime factor> ::=
<datetime primary> [ <time zone> ]
<datetime primary> ::=
<value expression primary>
| <datetime value function>
<time zone> ::=
AT <time zone specifier>
<time zone specifier> ::=
LOCAL
| TIME ZONE <interval value expression>
<length expression> ::=
<char length expression>
| <octet length expression>
| <bit length expression>
<char length expression> ::=
( CHAR_LENGTH | CHARACTER_LENGTH )
<left paren> <string value expression> <right paren>
<string value expression> ::=
<character value expression>
| <bit value expression>
<octet length expression> ::=
OCTET_LENGTH <left paren> <string value expression> <right paren>
<bit length expression> ::=
BIT_LENGTH <left paren> <string value expression> <right paren>
<null specification> ::=
NULL
<default specification> ::=
DEFAULT
<row value constructor list> ::=
<row value constructor element>
[ ( <comma> <row value constructor element> )... ]
<row subquery> ::= <subquery>
<comp op> ::=
<equals operator>
| <not equals operator>
| <less than operator>
| <greater than operator>
| <less than or equals operator>
| <greater than or equals operator>
<between predicate> ::=
<row value constructor> [ NOT ] BETWEEN
<row value constructor> AND <row value constructor>
<in predicate> ::=
<row value constructor>
[ NOT ] IN <in predicate value>
<in predicate value> ::=
<table subquery>
| <left paren> <in value list> <right paren>
<in value list> ::=
<value expression> ( <comma> <value expression> )...
<like predicate> ::=
<match value> [ NOT ] LIKE <pattern>
[ ESCAPE <escape character> ]
<match value> ::= <character value expression>
<pattern> ::= <character value expression>
<escape character> ::= <character value expression>
<null predicate> ::= <row value constructor>
IS [ NOT ] NULL
<quantified comparison predicate> ::=
<row value constructor> <comp op> <quantifier> <table subquery>
<quantifier> ::= <all> | <some>
<all> ::= ALL
<some> ::= SOME | ANY
<exists predicate> ::= EXISTS <table subquery>
<unique predicate> ::= UNIQUE <table subquery>
<match predicate> ::=
<row value constructor> MATCH [ UNIQUE ]
[ PARTIAL | FULL ] <table subquery>
<overlaps predicate> ::=
<row value constructor 1> OVERLAPS <row value constructor 2>
<row value constructor 1> ::= <row value constructor>
<row value constructor 2> ::= <row value constructor>
<truth value> ::=
TRUE
| FALSE
| UNKNOWN
<constraint attributes> ::=
<constraint check time> [ [ NOT ] DEFERRABLE ]
| [ NOT ] DEFERRABLE [ <constraint check time> ]
<constraint check time> ::=
INITIALLY DEFERRED
| INITIALLY IMMEDIATE
<table constraint definition> ::=
[ <constraint name definition> ]
<table constraint> [ <constraint attributes> ]
<table constraint> ::=
<unique constraint definition>
| <referential constraint definition>
| <check constraint definition>
<unique constraint definition> ::=
<unique specification> even in SQL3)
<unique specification>
<left paren> <unique column list> <right paren>
<unique column list> ::= <column name list>
<referential constraint definition> ::=
FOREIGN KEY
<left paren> <referencing columns> <right paren>
<references specification>
<referencing columns> ::=
<reference column list>
<module contents> ::=
<declare cursor>
| <dynamic declare cursor>
| <procedure>
<declare cursor> ::=
DECLARE <cursor name> [ INSENSITIVE ] [ SCROLL ] CURSOR
FOR <cursor specification>
<cursor name> ::= <identifier>
<cursor specification> ::=
<query expression> [ <order by clause> ]
[ <updatability clause> ]
<order by clause> ::=
ORDER BY <sort specification list>
<sort specification list> ::=
<sort specification> [ ( <comma> <sort specification> )... ]
<sort specification> ::=
<sort key> [ <collate clause> ] [ <ordering specification> ]
<sort key> ::=
<column name>
| <unsigned integer>
<ordering specification> ::= ASC | DESC
<updatability clause> ::=
FOR
( READ ONLY |
UPDATE [ OF <column name list> ] )
<dynamic declare cursor> ::=
DECLARE <cursor name> [ INSENSITIVE ] [ SCROLL ] CURSOR
FOR <statement name>
<statement name> ::= <identifier>
<procedure> ::=
PROCEDURE <procedure name>
<parameter declaration list> <semicolon>
<SQL procedure statement> <semicolon>
<procedure name> ::= <identifier>
<parameter declaration list> ::=
<left paren> <parameter declaration>
[ ( <comma> <parameter declaration> )... ] <right paren>
| <parameter declaration>...
<parameter declaration> ::=
<parameter name> <data type>
| <status parameter>
<status parameter> ::=
SQLCODE | SQLSTATE
<SQL procedure statement> ::=
<SQL schema statement>
| <SQL data statement>
| <SQL transaction statement>
| <SQL connection statement>
| <SQL session statement>
| <SQL dynamic statement>
| <SQL diagnostics statement>
<SQL schema statement> ::=
<SQL schema definition statement>
| <SQL schema manipulation statement>
<SQL schema definition statement> ::=
<schema definition>
| <table definition>
| <view definition>
| <grant statement>
| <domain definition>
| <character set definition>
| <collation definition>
| <translation definition>
| <assertion definition>
<schema definition> ::=
CREATE SCHEMA <schema name clause>
[ <schema character set specification> ]
[ <schema element>... ]
<schema name clause> ::=
<schema name>
| AUTHORIZATION <schema authorization identifier>
| <schema name> AUTHORIZATION
<schema authorization identifier>
<schema authorization identifier> ::=
<authorization identifier>
<schema character set specification> ::=
DEFAULT CHARACTER
SET <character set specification>
<schema element> ::=
<domain definition>
| <table definition>
| <view definition>
| <grant statement>
| <assertion definition>
| <character set definition>
| <collation definition>
| <translation definition>
<domain definition> ::=
CREATE DOMAIN <domain name>
[ AS ] <data type>
[ <default clause> ]
[ <domain constraint>... ]
[ <collate clause> ]
<domain constraint> ::=
[ <constraint name definition> ]
<check constraint definition> [ <constraint attributes> ]
<table definition> ::=
CREATE [ ( GLOBAL | LOCAL ) TEMPORARY ] TABLE
<table name>
<table element list>
[ ON COMMIT ( DELETE | PRESERVE ) ROWS ]
<view definition> ::=
CREATE VIEW <table name> [ <left paren> <view column list>
<right paren> ]
AS <query expression>
[ WITH [ <levels clause> ] CHECK OPTION ]
<view column list> ::= <column name list>
<levels clause> ::=
CASCADED | LOCAL
<grant statement> ::=
GRANT <privileges> ON <object name>
TO <grantee> [ ( <comma> <grantee> )... ]
[ WITH GRANT OPTION ]
<privileges> ::=
ALL PRIVILEGES
| <action list>
<action list> ::= <action> [ ( <comma> <action> )... ]
<action> ::=
SELECT
| DELETE
| INSERT [ <left paren> <privilege column list> <right paren> ]
| UPDATE [ <left paren> <privilege column list> <right paren> ]
| REFERENCES [ <left paren> <privilege column list> <right paren> ]
| USAGE
<privilege column list> ::= <column name list>
<object name> ::=
[ TABLE ] <table name>
| DOMAIN <domain name>
| COLLATION <collation name>
| CHARACTER SET <character set name>
| TRANSLATION <translation name>
<grantee> ::=
PUBLIC
| <authorization identifier>
<assertion definition> ::=
CREATE ASSERTION <constraint name> <assertion check>
[ <constraint attributes> ]
<assertion check> ::=
CHECK
<left paren> <search condition> <right paren>
<character set definition> ::=
CREATE CHARACTER SET <character set name>
[ AS ]
<character set source>
[ <collate clause> | <limited collation definition> ]
<character set source> ::=
GET <existing character set name>
<existing character set name> ::=
<standard character repertoire name>
| <implementation-defined character repertoire name>
| <schema character set name>
<schema character set name> ::= <character set name>
<limited collation definition> ::=
COLLATION FROM <collation source>
<collation source> ::=
<collating sequence definition>
| <translation collation>
<collating sequence definition> ::=
<external collation>
| <schema collation name>
| DESC <left paren> <collation name> <right paren>
| DEFAULT
<external collation> ::=
EXTERNAL <left paren> <quote> <external collation name> <quote> <right paren>
<external collation name> ::=
<standard collation name>
| <implementation-defined collation name>
<standard collation name> ::= <collation name>
<implementation-defined collation name> ::= <collation name>
<schema collation name> ::= <collation name>
<translation collation> ::=
TRANSLATION <translation name>
[ THEN COLLATION <collation name> ]
<collation definition> ::=
CREATE COLLATION <collation name> FOR
<character set specification>
FROM <collation source>
[ <pad attribute> ]
<pad attribute> ::=
NO PAD
| PAD SPACE
<translation definition> ::=
CREATE TRANSLATION <translation name>
FOR <source character set specification>
TO <target character set specification>
FROM <translation source>
<source character set specification> ::= <character set specification>
<target character set specification> ::= <character set specification>
<translation source> ::=
<translation specification>
<translation specification> ::=
<external translation>
| IDENTITY
| <schema translation name>
<external translation> ::=
EXTERNAL <left paren> <quote> <external translation name> <quote> <right paren>
<external translation name> ::=
<standard translation name>
| <implementation-defined translation name>
<standard translation name> ::= <translation name>
<implementation-defined translation name> ::= <translation name>
<schema translation name> ::= <translation name>
<SQL schema manipulation statement> ::=
<drop schema statement>
| <alter table statement>
| <drop table statement>
| <drop view statement>
| <revoke statement>
| <alter domain statement>
| <drop domain statement>
| <drop character set statement>
| <drop collation statement>
| <drop translation statement>
| <drop assertion statement>
<drop schema statement> ::=
DROP SCHEMA <schema name> <drop behavior>
<drop behavior> ::= CASCADE | RESTRICT
<alter table statement> ::=
ALTER TABLE <table name> <alter table action>
<alter table action> ::=
<add column definition>
| <alter column definition>
| <drop column definition>
| <add table constraint definition>
| <drop table constraint definition>
<add column definition> ::=
ADD [ COLUMN ] <column definition>
<alter column definition> ::=
ALTER [ COLUMN ] <column name> <alter column action>
<alter column action> ::=
<set column default clause>
| <drop column default clause>
<set column default clause> ::=
SET <default clause>
<drop column default clause> ::=
DROP DEFAULT
<drop column definition> ::=
DROP [ COLUMN ] <column name> <drop behavior>
<add table constraint definition> ::=
ADD <table constraint definition>
<drop table constraint definition> ::=
DROP CONSTRAINT <constraint name> <drop behavior>
<drop table statement> ::=
DROP TABLE <table name> <drop behavior>
<drop view statement> ::=
DROP VIEW <table name> <drop behavior>
<revoke statement> ::=
REVOKE [ GRANT OPTION FOR ]
<privileges>
ON <object name>
FROM <grantee> [ ( <comma> <grantee> )... ] <drop behavior>
<alter domain statement> ::=
ALTER DOMAIN <domain name> <alter domain action>
<alter domain action> ::=
<set domain default clause>
| <drop domain default clause>
| <add domain constraint definition>
| <drop domain constraint definition>
<set domain default clause> ::= SET <default clause>
<drop domain default clause> ::= DROP DEFAULT
<add domain constraint definition> ::=
ADD <domain constraint>
<drop domain constraint definition> ::=
DROP CONSTRAINT <constraint name>
<drop domain statement> ::=
DROP DOMAIN <domain name> <drop behavior>
<drop character set statement> ::=
DROP CHARACTER SET <character set name>
<drop collation statement> ::=
DROP COLLATION <collation name>
<drop translation statement> ::=
DROP TRANSLATION <translation name>
<drop assertion statement> ::=
DROP ASSERTION <constraint name>
<SQL data statement> ::=
<open statement>
| <fetch statement>
| <close statement>
| <select statement: single row>
| <SQL data change statement>
<open statement> ::=
OPEN <cursor name>
<fetch statement> ::=
FETCH [ [ <fetch orientation> ] FROM ]
<cursor name> INTO <fetch target list>
<fetch orientation> ::=
NEXT
| PRIOR
| FIRST
| LAST
| ( ABSOLUTE | RELATIVE ) <simple value specification>
<simple value specification> ::=
<parameter name>
| <embedded variable name>
| <literal>
<fetch target list> ::=
<target specification> [ ( <comma> <target specification> )... ]
<target specification> ::=
<parameter specification>
| <variable specification>
<close statement> ::=
CLOSE <cursor name>
<select statement: single row> ::=
SELECT [ <set quantifier> ] <select list>
INTO <select target list>
<table expression>
<select target list> ::=
<target specification> [ ( <comma> <target specification> )... ]
<SQL data change statement> ::=
<delete statement: positioned>
| <delete statement: searched>
| <insert statement>
| <update statement: positioned>
| <update statement: searched>
<delete statement: positioned> ::=
DELETE FROM <table name>
WHERE CURRENT OF <cursor name>
<delete statement: searched> ::=
DELETE FROM <table name>
[ WHERE <search condition> ]
<insert statement> ::=
INSERT INTO <table name>
<insert columns and source>
<insert columns and source> ::=
[ <left paren> <insert column list> <right paren> ]
<query expression>
| DEFAULT VALUES
<insert column list> ::= <column name list>
<update statement: positioned> ::=
UPDATE <table name>
SET <set clause list>
WHERE CURRENT OF <cursor name>
<set clause list> ::=
<set clause> [ ( <comma> <set clause> )... ]
<set clause> ::=
<object column> <equals operator> <update source>
<object column> ::= <column name>
<update source> ::=
<value expression>
| <null specification>
| DEFAULT
<update statement: searched> ::=
UPDATE <table name>
SET <set clause list>
[ WHERE <search condition> ]
<SQL transaction statement> ::=
<set transaction statement>
| <set constraints mode statement>
| <commit statement>
| <rollback statement>
<set transaction statement> ::=
SET TRANSACTION <transaction mode>
[ ( <comma> <transaction mode> )... ]
<transaction mode> ::=
<isolation level>
| <transaction access mode>
| <diagnostics size>
<isolation level> ::=
ISOLATION LEVEL <level of isolation>
<level of isolation> ::=
READ UNCOMMITTED
| READ COMMITTED
| REPEATABLE READ
| SERIALIZABLE
<transaction access mode> ::=
READ ONLY
| READ WRITE
<diagnostics size> ::=
DIAGNOSTICS SIZE <number of conditions>
<number of conditions> ::= <simple value specification>
<set constraints mode statement> ::=
SET CONSTRAINTS <constraint name list>
( DEFERRED | IMMEDIATE )
<constraint name list> ::=
ALL
| <constraint name> [ ( <comma> <constraint name> )... ]
<commit statement> ::=
COMMIT [ WORK ]
<rollback statement> ::=
ROLLBACK [ WORK ]
<SQL connection statement> ::=
<connect statement>
| <set connection statement>
| <disconnect statement>
<connect statement> ::=
CONNECT TO <connection target>
<connection target> ::=
<SQL-server name>
[ AS <connection name> ]
correspondence with Tony Gordon)
[ USER <user name> ]
| DEFAULT
<SQL-server name> ::= <simple value specification>
<connection name> ::= <simple value specification>
<user name> ::= <simple value specification>
<set connection statement> ::=
SET CONNECTION <connection object>
<connection object> ::=
DEFAULT
| <connection name>
<disconnect statement> ::=
DISCONNECT <disconnect object>
<disconnect object> ::=
<connection object>
| ALL
| CURRENT
<SQL session statement> ::=
<set catalog statement>
| <set schema statement>
| <set names statement>
| <set session authorization identifier statement>
| <set local time zone statement>
<set catalog statement> ::=
SET CATALOG <value specification>
<value specification> ::=
<literal>
| <general value specification>
<set schema statement> ::=
SET SCHEMA <value specification>
<set names statement> ::=
SET NAMES <value specification>
<set session authorization identifier statement> ::=
SET SESSION AUTHORIZATION
<value specification>
<set local time zone statement> ::=
SET TIME ZONE
<set time zone value>
<set time zone value> ::=
<interval value expression>
| LOCAL
<SQL dynamic statement> ::=
<system descriptor statement>
| <prepare statement>
| <deallocate prepared statement>
| <describe statement>
| <execute statement>
| <execute immediate statement>
| <SQL dynamic data statement>
<system descriptor statement> ::=
<allocate descriptor statement>
| <deallocate descriptor statement>
| <set descriptor statement>
| <get descriptor statement>
<allocate descriptor statement> ::=
ALLOCATE DESCRIPTOR <descriptor name>
[ WITH MAX <occurrences> ]
<descriptor name> ::=
[ <scope option> ] <simple value specification>
<scope option> ::=
GLOBAL
| LOCAL
<occurrences> ::= <simple value specification>
<deallocate descriptor statement> ::=
DEALLOCATE DESCRIPTOR <descriptor name>
<set descriptor statement> ::=
SET DESCRIPTOR <descriptor name>
<set descriptor information>
<set descriptor information> ::=
<set count>
| VALUE <item number>
<set item information> [ ( <comma> <set item information> )... ]
<set count> ::=
COUNT <equals operator> <simple value specification 1>
<simple value specification 1> ::= <simple value specification>
<item number> ::= <simple value specification>
<set item information> ::=
<descriptor item name> <equals operator> <simple value specification 2>
<descriptor item name> ::=
TYPE
| LENGTH
| OCTET_LENGTH
| RETURNED_LENGTH
| RETURNED_OCTET_LENGTH
| PRECISION
| SCALE
| DATETIME_INTERVAL_CODE
| DATETIME_INTERVAL_PRECISION
| NULLABLE
| INDICATOR
| DATA
| NAME
| UNNAMED
| COLLATION_CATALOG
| COLLATION_SCHEMA
| COLLATION_NAME
| CHARACTER_SET_CATALOG
| CHARACTER_SET_SCHEMA
| CHARACTER_SET_NAME
<simple value specification 2> ::= <simple value specification>
<item number> ::= <simple value specification>
<get descriptor statement> ::=
GET DESCRIPTOR <descriptor name> <get descriptor information>
<get descriptor information> ::=
<get count>
| VALUE <item number>
<get item information> [ ( <comma> <get item information> )... ]
<get count> ::=
<simple target specification 1> <equals operator>
COUNT
<simple target specification 1> ::= <simple target specification>
<simple target specification> ::=
<parameter name>
| <embedded variable name>
<get item information> ::=
<simple target specification 2> <equals operator> <descriptor item name>>
<simple target specification 2> ::= <simple target specification>
<prepare statement> ::=
PREPARE <SQL statement name> FROM <SQL statement variable>
<SQL statement name> ::=
<statement name>
| <extended statement name>
<extended statement name> ::=
[ <scope option> ] <simple value specification>
<SQL statement variable> ::= <simple value specification>
<deallocate prepared statement> ::=
DEALLOCATE PREPARE <SQL statement name>
<describe statement> ::=
<describe input statement>
| <describe output statement>
<describe input statement> ::=
DESCRIBE INPUT <SQL statement name> <using descriptor>
<using descriptor> ::=
( USING | INTO ) SQL DESCRIPTOR <descriptor name>
<describe output statement> ::=
DESCRIBE [ OUTPUT ] <SQL statement name> <using descriptor>
<execute statement> ::=
EXECUTE <SQL statement name>
[ <result using clause> ]
[ <parameter using clause> ]
<result using clause> ::= <using clause>
<using clause> ::=
<using arguments>
| <using descriptor>
<using arguments> ::=
( USING | INTO ) <argument> [ ( <comma> <argument> )... ]
<argument> ::= <target specification>
<parameter using clause> ::= <using clause>
<execute immediate statement> ::=
EXECUTE IMMEDIATE <SQL statement variable>
<SQL dynamic data statement> ::=
<allocate cursor statement>
| <dynamic open statement>
| <dynamic fetch statement>
| <dynamic close statement>
| <dynamic delete statement: positioned>
| <dynamic update statement: positioned>
<allocate cursor statement> ::=
ALLOCATE <extended cursor name> [ INSENSITIVE ]
[ SCROLL ] CURSOR
FOR <extended statement name>
<extended cursor name> ::=
[ <scope option> ] <simple value specification>
<dynamic open statement> ::=
OPEN <dynamic cursor name> [ <using clause> ]
<dynamic cursor name> ::=
<cursor name>
| <extended cursor name>
<dynamic fetch statement> ::=
FETCH [ [ <fetch orientation> ] FROM ] <dynamic cursor name>
<using clause>
<dynamic close statement> ::=
CLOSE <dynamic cursor name>
<dynamic delete statement: positioned> ::=
DELETE FROM <table name>
WHERE CURRENT OF
<dynamic cursor name>
<dynamic update statement: positioned> ::=
UPDATE <table name>
SET <set clause>
[ ( <comma> <set clause> )... ]
WHERE CURRENT OF
<dynamic cursor name>
<SQL diagnostics statement> ::=
<get diagnostics statement>
<get diagnostics statement> ::=
GET DIAGNOSTICS <sql diagnostics information>
<sql diagnostics information> ::=
<statement information>
| <condition information>
<statement information> ::=
<statement information item> [ ( <comma> <statement information item> )... ]
<statement information item> ::=
<simple target specification> <equals operator> <statement information item name>
<statement information item name> ::=
NUMBER
| MORE
| COMMAND_FUNCTION
| DYNAMIC_FUNCTION
| ROW_COUNT
<condition information> ::=
EXCEPTION <condition number>
<condition information item> [ ( <comma> <condition information item> )... ]
<condition number> ::= <simple value specification>
<condition information item> ::=
<simple target specification> <equals operator> <condition information item name>
<condition information item name> ::=
CONDITION_NUMBER
| RETURNED_SQLSTATE
| CLASS_ORIGIN
| SUBCLASS_ORIGIN
| SERVER_NAME
| CONNECTION_NAME
| CONSTRAINT_CATALOG
| CONSTRAINT_SCHEMA
| CONSTRAINT_NAME
| CATALOG_NAME
| SCHEMA_NAME
| TABLE_NAME
| COLUMN_NAME
| CURSOR_NAME
| MESSAGE_TEXT
| MESSAGE_LENGTH
| MESSAGE_OCTET_LENGTH
<embedded SQL host program> ::=
<embedded SQL Ada program>
| <embedded SQL C program>
| <embedded SQL COBOL program>
| <embedded SQL Fortran program>
| <embedded SQL MUMPS program>
| <embedded SQL Pascal program>
| <embedded SQL PL/I program>
<embedded SQL Ada program> ::= !! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL C program> ::=
!! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL COBOL program> ::= !! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL Fortran program> ::=
!! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL MUMPS program> ::= !! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL Pascal program> ::=
!! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL PL/I program> ::= !! <EMPHASIS>(See the Syntax Rules.)
<embedded SQL declare section> ::=
<embedded SQL begin declare>
[ <embedded character set declaration> ]
[ <host variable definition>... ]
<embedded SQL end declare>
| <embedded SQL MUMPS declare>
<embedded SQL begin declare> ::=
<SQL prefix> BEGIN DECLARE SECTION
[ <SQL terminator> ]
<SQL prefix> ::=
EXEC SQL
| <ampersand>SQL<left paren>
<SQL terminator> ::=
END-EXEC
| <semicolon>
| <right paren>
<embedded character set declaration> ::=
SQL NAMES ARE <character set specification>
<host variable definition> ::=
<Ada variable definition>
| <C variable definition>
| <COBOL variable definition>
| <Fortran variable definition>
| <MUMPS variable definition>
| <Pascal variable definition>
| <PL/I variable definition>
<Ada variable definition> ::=
<Ada host identifier> [ ( <comma> <Ada host identifier> )... ] :
<Ada type specification> [ <Ada initial value> ]
<Ada type specification> ::=
<Ada qualified type specification>
| <Ada unqualified type specification>
<Ada qualified type specification> ::=
SQL_STANDARD.CHAR [ CHARACTER SET
[ IS ] <character set specification> ]
<left paren> 1 <double period> <length> <right paren>
| SQL_STANDARD.BIT
<left paren> 1 <double period> <length> <right paren>
| SQL_STANDARD.SMALLINT
| SQL_STANDARD.INT
| SQL_STANDARD.REAL
| SQL_STANDARD.DOUBLE_PRECISION
| SQL_STANDARD.SQLCODE_TYPE
| SQL_STANDARD.SQLSTATE_TYPE
| SQL_STANDARD.INDICATOR_TYPE
<Ada unqualified type specification> ::=
CHAR
<left paren> 1 <double period> <length> <right paren>
| BIT
<left paren> 1 <double period> <length> <right paren>
| SMALLINT
| INT
| REAL
| DOUBLE_PRECISION
| SQLCODE_TYPE
| SQLSTATE_TYPE
| INDICATOR_TYPE
<Ada initial value> ::=
<Ada assignment operator> <character representation>...
<Ada assignment operator> ::= <colon><equals operator>
<C variable definition> ::=
[ <C storage class> ]
[ <C class modifier> ]
<C variable specification>
<semicolon>
<C storage class> ::=
auto
| extern
| static
<C class modifier> ::= const | volatile
<C variable specification> ::=
<C numeric variable>
| <C character variable>
| <C derived variable>
<C numeric variable> ::=
( long | short | float | double )
<C host identifier> [ <C initial value> ]
[ ( <comma> <C host identifier> [ <C initial value> ] )... ]
<C initial value> ::=
<equals operator> <character representation>...
<C character variable> ::=
char [ CHARACTER SET
[ IS ] <character set specification> ]
<C host identifier>
<C array specification> [ <C initial value> ]
[ ( <comma> <C host identifier>
<C array specification>
[ <C initial value> ] )... ]
<C array specification> ::=
<left bracket> <length> <right bracket>
<C derived variable> ::=
<C VARCHAR variable>
| <C bit variable>
<C VARCHAR variable> ::=
VARCHAR [ CHARACTER SET [ IS ]
<character set specification> ]
<C host identifier>
<C array specification> [ <C initial value> ]
[ ( <comma> <C host identifier>
<C array specification>
[ <C initial value> ] )... ]
<C bit variable> ::=
BIT <C host identifier>
<C array specification> [ <C initial value> ]
[ ( <comma> <C host identifier>
<C array specification>
[ <C initial value> ] )... ]
<COBOL variable definition> ::=
(01|77) <COBOL host identifier> <COBOL type specification>
[ <character representation>... ] <period>
<COBOL type specification> ::=
<COBOL character type>
| <COBOL bit type>
| <COBOL numeric type>
| <COBOL integer type>
<COBOL character type> ::=
[ CHARACTER SET [ IS ]
<character set specification> ]
( PIC | PICTURE ) [ IS ] ( X [ <left paren> <length> <right paren> ] )...
<COBOL bit type> ::=
( PIC | PICTURE ) [ IS ]
( B [ <left paren> <length> <right paren> ] )...
<COBOL numeric type> ::=
( PIC | PICTURE ) [ IS ]
S <COBOL nines specification>
[ USAGE [ IS ] ] DISPLAY SIGN LEADING SEPARATE
<COBOL nines specification> ::=
<COBOL nines> [ V [ <COBOL nines> ] ]
| V <COBOL nines>
<COBOL nines> ::= ( 9 [ <left paren> <length> <right paren> ] )...
<COBOL integer type> ::=
<COBOL computational integer>
| <COBOL binary integer>
<COBOL computational integer> ::=
( PIC | PICTURE ) [ IS ] S<COBOL nines>
[ USAGE [ IS ] ] ( COMP | COMPUTATIONAL )
<COBOL binary integer> ::=
( PIC | PICTURE ) [ IS ] S<COBOL nines>
[ USAGE [ IS ] ] BINARY
<Fortran variable definition> ::=
<Fortran type specification>
<Fortran host identifier>
[ ( <comma> <Fortran host identifier> )... ]
<Fortran type specification> ::=
CHARACTER [ <asterisk> <length> ]
[ CHARACTER SET [ IS ]
<character set specification> ]
| BIT [ <asterisk> <length> ]
| INTEGER
| REAL
| DOUBLE PRECISION
<MUMPS variable definition> ::=
( <MUMPS numeric variable> | <MUMPS character variable> )
<semicolon>
<MUMPS numeric variable> ::=
<MUMPS type specification>
<MUMPS host identifier> [ ( <comma> <MUMPS host identifier> )... ]
<MUMPS type specification> ::=
INT
| DEC
[ <left paren> <precision> [ <comma> <scale> ] <right paren> ]
| REAL
<MUMPS character variable> ::=
VARCHAR <MUMPS host identifier> <MUMPS length specification>
[ ( <comma> <MUMPS host identifier> <MUMPS length specification> )... ]
<MUMPS length specification> ::=
<left paren> <length> <right paren>
<Pascal variable definition> ::=
<Pascal host identifier> [ ( <comma> <Pascal host identifier> )... ] <colon>
<Pascal type specification> <semicolon>
<Pascal type specification> ::=
PACKED ARRAY
<left bracket> 1 <double period> <length> <right bracket>
OF CHAR
[ CHARACTER SET [ IS ]
<character set specification> ]
| PACKED ARRAY
<left bracket> 1 <double period> <length> <right bracket>
OF BIT
| INTEGER
| REAL
| CHAR [ CHARACTER SET
[ IS ] <character set specification> ]
| BIT
<PL/I variable definition> ::=
(DCL | DECLARE)
( <PL/I host identifier>
| <left paren> <PL/I host identifier>
[ ( <comma> <PL/I host identifier> )... ] <right paren> )
<PL/I type specification>
[ <character representation>... ] <semicolon>
<PL/I type specification> ::=
( CHAR | CHARACTER ) [ VARYING ]
<left paren><length><right paren>
[ CHARACTER SET
[ IS ] <character set specification> ]
| BIT [ VARYING ] <left paren><length><right paren>
| <PL/I type fixed decimal> <left paren> <precision>
[ <comma> <scale> ] <right paren>
| <PL/I type fixed binary> [ <left paren> <precision> <right paren> ]
| <PL/I type float binary> <left paren> <precision> <right paren>
<PL/I type fixed decimal> ::=
( DEC | DECIMAL ) FIXED
| FIXED ( DEC | DECIMAL )
<PL/I type fixed binary> ::=
( BIN | BINARY ) FIXED
| FIXED ( BIN | BINARY )
<PL/I type float binary> ::=
( BIN | BINARY ) FLOAT
| FLOAT ( BIN | BINARY )
<embedded SQL end declare> ::=
<SQL prefix> END DECLARE SECTION
[ <SQL terminator> ]
<embedded SQL MUMPS declare> ::=
<SQL prefix>
BEGIN DECLARE SECTION
[ <embedded character set declaration> ]
[ <host variable definition>... ]
END DECLARE SECTION
<SQL terminator>
<embedded SQL statement> ::=
<SQL prefix>
<statement or declaration>
[ <SQL terminator> ]
<statement or declaration> ::=
<declare cursor>
| <dynamic declare cursor>
| <temporary table declaration>
| <embedded exception declaration>
| <SQL procedure statement>
<embedded exception declaration> ::=
WHENEVER <condition> <condition action>
<condition> ::=
SQLERROR | NOT FOUND
<condition action> ::=
CONTINUE | <go to>
<go to> ::=
( GOTO | GO TO ) <goto target>
<goto target> ::=
<host label identifier>
| <unsigned integer>
| <host PL/I label variable>
<host label identifier> ::= !!<EMPHASIS>(See the Syntax Rules.)
<host PL/I label variable> ::= !!<EMPHASIS>(See the Syntax Rules.)
<preparable statement> ::=
<preparable SQL data statement>
| <preparable SQL schema statement>
| <preparable SQL transaction statement>
| <preparable SQL session statement>
| <preparable implementation-defined statement>
<preparable SQL data statement> ::=
<delete statement: searched>
| <dynamic single row select statement>
| <insert statement>
| <dynamic select statement>
| <update statement: searched>
| <preparable dynamic delete statement: positioned>
| <preparable dynamic update statement: positioned>
<dynamic single row select statement> ::= <query specification>
<dynamic select statement> ::= <cursor specification>
<preparable dynamic delete statement: positioned> ::=
DELETE [ FROM <table name> ]
WHERE CURRENT OF <cursor name>
<preparable dynamic update statement: positioned> ::=
UPDATE [ <table name> ]
SET <set clause list>
WHERE CURRENT OF <cursor name>
<preparable SQL schema statement> ::=
<SQL schema statement>
<preparable SQL transaction statement> ::=
<SQL transaction statement>
<preparable SQL session statement> ::=
<SQL session statement>
<preparable implementation-defined statement> ::=
!! <EMPHASIS>(See the Syntax Rules.)
<direct SQL statement> ::=
<directly executable statement> <semicolon>
<directly executable statement> ::=
<direct SQL data statement>
| <SQL schema statement>
| <SQL transaction statement>
| <SQL connection statement>
| <SQL session statement>
| <direct implementation-defined statement>
<direct SQL data statement> ::=
<delete statement: searched>
| <direct select statement: multiple rows>
| <insert statement>
| <update statement: searched>
| <temporary table declaration>
<direct select statement: multiple rows> ::=
<query expression> [ <order by clause> ]
<direct implementation-defined statement> ::=
!!<EMPHASIS>(See the Syntax Rules)
<SQL object identifier> ::=
<SQL provenance> <SQL variant>
<SQL provenance> ::= <arc1> <arc2> <arc3>
<arc1> ::= iso | 1 | iso <left paren> 1 <right paren>
<arc2> ::= standard | 0 | standard <left paren> 0 <right paren>
<arc3> ::= 9075
<SQL variant> ::= <SQL edition> <SQL conformance>
<SQL edition> ::= <1987> | <1989> | <1992>
<1987> ::= 0 | edition1987 <left paren> 0 <right paren>
<1989> ::= <1989 base> <1989 package>
<1989 base> ::= 1 | edition1989 <left paren> 1 <right paren>
<1989 package> ::= <integrity no> | <integrity yes>
<integrity no> ::= 0 | IntegrityNo <left paren> 0 <right paren>
<integrity yes> ::= 1 | IntegrityYes <left paren> 1 <right paren>
<1992> ::= 2 | edition1992 <left paren> 2 <right paren>
<SQL conformance> ::= <low> | <intermediate> | <high>
<low> ::= 0 | Low <left paren> 0 <right paren>
<intermediate> ::= 1 | Intermediate <left paren> 1 <right paren>
<high> ::= 2 | High <left paren> 2 <right paren>
SQL tutorial is also distributed with PostgreSQL. The SQL tutorial scripts is in the directory src/tutorial
The SQL tutorial for beginners can be found at
Comments or suggestions? Mail toIf you are planning to use PostgreSQL on Linux, and need help in installing Linux, then please visit the pointers given in this Appendix. They cover the following topics -