select A,B,C,D=(select count(*) from 表 where c=a.a and b=a.b

select A,B,C,D=(select count(*) from 表 where c=a.a and b=a.b select A.a,b,c,d from A,B where A.a=B.a and f='1' select count(*) from v$process a,v$session b where a.addr = select distinct A.* from A,B where A.id = B.g_id and A.fwzid SQL语句理解 select * from B where (select count(1) as num from A select count(*) as total from ddcm_news where key=a select * into b from a where 11 select count(c) from (select b from TUserBankLogSum b group select ** from A where A.id in (select id from B where ****) sql函数,select count(A.abc) as sum from A left join B on A.id= select a,b from 表名 group by a,b order by count(*) desc select * from a union select * from b 能详细说下么