select * from a inner join b on a.id = b.aid
和select * from a,b where a.id = b.aid
效果一样吗?如果一样的话,用哪一个效果更好?为什么?
PHP中文网2017-04-17 14:46:34
select * from a inner join b on a.id = b.id This is an inner join
select * from a, b where a.id=b.id This is an equijoin
The effect of inner join and equivalent join is the same, and the execution efficiency is the same