…in set, 1 warning (0.00 sec) mysql> show warnings; +——-+——+——————————————————————————-+ | Level | Code | Message | +——-+——+——————————————————————————-+ | Note | 1003 | select `test…
Post: Extended EXPLAIN
July 24, 2006 By 9 Comments
… | +—-+————-+——–+——-+—————+———+———+——+——–+————-+ 1 row in set, 1 warning (0.02 sec) mysql> show warnings \G *************************** 1. row *************************** Level: Note Code: 1003 Message: select `test`.`sbtest`.`id` AS…
Post: JOIN Performance & Charsets
October 21, 2008 By 2 Comments
… index 2 rows in set, 1 warning (0.00 sec) mysql> SHOW WARNINGS\G *************************** 1. row *************************** Level: Note Code: 1003 Message: select sql_no_cache… index 2 rows in set, 1 warning (0.00 sec) mysql> SHOW WARNINGS\G *************************** 1. row *************************** Level: Note Code: 1003 Message: select sql_no_cache…
Comment: COUNT(*) vs COUNT(col)
April 19, 2007 By 45 Comments
… 1 row in set, 1 warning (0.00 sec) mysql> show warnings; +——-+——+———————————————————+ | Level | Code | Message | +——-+——+———————————————————+ | Note | 1003 | select count(0) AS `count… 1 row in set, 1 warning (0.00 sec) mysql> show warnings; +——-+——+———————————————————+ | Level | Code | Message | +——-+——+———————————————————+ | Note | 1003 | select count(1) AS `count…
Post: A workaround for the performance problems of TEMPTABLE views
May 19, 2010 By 7 Comments
… then MySQL will let us use the MERGE algorithm. Notice that there are no warnings: mysql> create…Code | Message | +——-+——+———————————————————————————————————————————+ | Note | 1003 | select `test`.`t2`.`c1`…
Comment: EXPLAIN EXTENDED can tell you all kinds of interesting things
June 30, 2010 By 7 Comments
…warning (0.01 sec) mysql> show warnings; …| +——-+——+—————————————————————————————————————————————————————————-+ | Note | 1003 | select …
