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假设供应商S和供应情况SPJ的关系模式分别为：S(Sno, Sname, Status, City)和SPJ(Sno, Pno, Jno, Qty)。SQL语句______不能正确地查询出“零件号Pno等于'P3'的供应商名Sname”。
A．SELECT DISTINCT Sname FROM S WHERE EXISTS (SELECT* FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')
B．SELECT DISTINCT Sname FROM S WHERERE 0＜ (SELECT COUNT (*) FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')
C．SELECT Sname FROM S WHERE EXISTS (SELECT* FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')
D．SELECT Sname FROM S, SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3') GROUP BY Sname
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