1、select * from A a left join B b on a.aid=b.bid where a.aid > 10
2、select * from (select * from A where aid > 10) a left join (select * from B where bid > 10) b on a.aid=b.bid
1、select * from A a left join B b on a.aid=b.bid where a.aid > 10
2、select * from (select * from A where aid > 10) a left join (select * from B where bid > 10) b on a.aid=b.bid