sql語(yǔ)句查詢語(yǔ)法？1:select s#，sn from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and c.cn="稅收基礎(chǔ)"2:select sn，sd f

sql語(yǔ)句查詢語(yǔ)法？

1:select s#，sn from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and c.cn="稅收基礎(chǔ)"2:select sn，sd from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and c.c#="C2"3:select sn，sd from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and c.c#!="C5"4:select * from (select sn，sd，count(s.*) as cc from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and s.s# group by sn，sd) as tt where tt.cc=(select count(*) from c)5: select count(tt.*) from (select s#，sn from s，c，sc where s.s#=sc.s# and c.c#=sc.c# group by s#，sn) as tt6:select * from (select sn，sd，count(s.*) as cc from s，c，sc where s.s#=sc.s# and c.c#=sc.c# and s.s# group by sn，sd) as tt where tt.cc>=5) 剛寫的，希望能幫到你。