摘要：
declare @a table(a int,b int)declare @b table(a int,b int)insert @a values(1,1)insert @a values(2,2)insert @b values(1,1)insert @b values(3,3)select * from @a select * from @b--左:select * from @a Aa left join @b Bb on Aa.a=Bb.a--右：select * from @a Aa right join @b Bb on Aa.a=Bb.a--内select * from @a 阅读全文
