| 知乎專欄 ｜ 多維度架構 |
where 條件的順序影響查詢速度
EXPLAIN select *,from_unixtime(sendtime) from sms where id='461539' and content like '13%'; /* 0 rows affected, 1 rows found. Duration for 1 query: 0.218 sec. */ EXPLAIN select *,from_unixtime(sendtime) from sms where content like '13%' and id='461539'; /* 0 rows affected, 1 rows found. Duration for 1 query: 0.717 sec. */