C.REATE TABLE SP (Sno CHAR(5),
Pno CHAR(6),
Status CHAR(8),
Qty NUMERIC(9),(33)(Sno,Pno),(34)(Sno),(35)(Pno));
查询供应了“红”色零件的供应商号、零件号和数量(Qty)的元组演算表达式为: {t|((36)∧u[1]=v[1]∧v[2]=w[1]∧w[3]='红'∧(37))}
A.FOREIGN KEY
B.PRIMARY KEY
C.FOREIGN KEY(Sno)REFERENCES S
D.FOREIGN KEY(Pno)REFERENCES P