你的语句是怎么写的?表之间有关系吗?select * from a
join b on a.id=b.id
join c on a.id=c.id
where 条件的速度快过:select * from a,b,c
where a.id=b.id and a.id=c.id and 条件
join b on a.id=b.id
join c on a.id=c.id
where 条件的速度快过:select * from a,b,c
where a.id=b.id and a.id=c.id and 条件
2:参考:
性能优化:
http://expert.csdn.net/Expert/topic/2331/2331693.xml?temp=.6327021