问题详情

“找出北京供应商供应的所有零件信息”的SELECT语句是( )。 A.SELECT*FROM S WHERE CITY=’北京’ B.STLECT SNO,SNAME FROM S WHERE CITY=’北京’ C.SELECT P.*FROM S,P WHERE S.CITY=’北京’ AND S.SNO=SJP.SNO AND SJP.PNO=P.PNO D.SELECT P.*FROM P,S,SJP WHERE S.CITY=’北京’ AND S.SNO=SJP.SNO AND SJP.PNO=P.PNO


A、SELECT*FROM S WHERE CITY=’北京’

B、STLECT SNO,SNAME FROM S WHERE CITY=’北京’

C、SELECT P.*FROM S,P WHERE S.CITY=’北京’ AND S.SNO=SJP.SNO AND SJP.PNO=P.PNO

D、SELECT P.*FROM P,S,SJP WHERE S.CITY=’北京’ AND S.SNO=SJP.SNO AND SJP.PNO=P.PNO

时间:2022-01-02 22:18 关键词:

答案解析

D
北京供应商涉及到CITY属性,要用关系S,零件信息要用到关系P,而这两个关系需用关系SJP联系起来,所以FROM后面跟三个关系P,S,SJP。