Go to the first , previous , next , last section, table of contents . ... In MySQL 3.20, the maximum size of the temporary table was record_buffer*16 , so if you are using this version, you have to increase the value of record_buffer . ... This can be done with the following code: mysql> LOCK TABLES real_table WRITE, insert_table WRITE; mysql> insert into real_table select * from insert_table; mysql> delete from insert_table; mysql> UNLOCK TABLES; . ... See section 9.4 MySQL table types . ...