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某数据库中有供应商关系S和零件关系P,其中:供应商关系模式S(Sno,Sname,Szip,City)中的属性分别表示:供应商代码、供应商名、邮编、供应商所在城市;零件关系模式P(Pno,Pname,Color, Weisht,City)中的属性分别表示:零件号、零件名、颜色、重量、产地。要求一个供应商可以供应多种零件,而一种零件可以由多个供应商供应。请将以下(62)空缺处的SQL语句补充完整。    CREATE TABLE SP(Sno CHAR(5),                  Pno CHAR(6),                  Status CHAR(8),                  QLy NUMERIC(9),                  PRIMARY KEY(Sno,Pno) (62);

  • A.PRIMARY KEY (Sno) REFERENCE S (Sno),FOREIGN KEY (Pno) REFERENCES P (Pno)
  • B.FOREIGN KEY (Sno) REFERENCE S (Sno),PRIMARY KEY (Pno) REFERENCES P (Pno)
  • C.FOREIGN KEY (Sno) REFERENCE S (Sno),FOREIGN KEY (Pno) REFERENCES P (Pno)
  • D.PRIMARY KEY (Sno) REFERENCE S (Sno),PRIMARY KEY (Pno) REFERENCES P (Pno)
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