如下表所示，有两个关系E和F，若它们经过某一关系运算后的结果为{计算机学院}，这一关系运算为（ ）。
- A.E*F
- B.F*E
- C.E/F
- D.F/E
正确答案及解析
正确答案
解析
给定关系R(X，Y)和S(Y，Z)，其中X，Y，Z为属性组。R中的Y与S中的Y可以有不同的属性名，但必须出自相同的域集。R与S的除运算得到一个新的关系P(X)，P是R中满足下列条件的元组在X属性列上的投影：元组在X上分量值x的象集Yx包含S在Y上投影的集合，记作：
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