--存在 select * from A where exists(select 1 from B where A.a = B.b) --不存在 select * from A where not exists(select 1 from B where A.a = B.b)
转载于:https://www.cnblogs.com/lydg/p/11362343.html
--存在 select * from A where exists(select 1 from B where A.a = B.b) --不存在 select * from A where not exists(select 1 from B where A.a = B.b)
转载于:https://www.cnblogs.com/lydg/p/11362343.html