31. 以下哪項不是有效的SQL指令?
(A)SELECT * FROM Lawyers WHERE firmName LIKE '% and %';
(B)SELECT COUNT(*) FROM Firms WHERE employees < 100;
(C)SELECT firmLoc, COUNT(*) FROM Firms WHERE employees < 100;
(D)SELECT firmLoc, COUNT(*) FROM Firms WHERE employees < 100 GROUP BY firmLoc;

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統計: A(39), B(21), C(63), D(39), E(0) #2388706

詳解 (共 2 筆)

#5019237
從以下兩條說明,可以知道,如果selec...
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5
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#4571408
COUNT(*)  要搭 GROUP B...
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3
0