第9題: 等價(jià)于修了和01相同顆數(shù),01沒(méi)有修他們就沒(méi)有修
select sid from sc where CId not in(select cid from course where cid not in (select cid from sc where sid = '01')) group by sid
having count(sid) = (select count(sid) from sc where sid = '01');
50道SQL練習(xí)題及答案與詳細(xì)分析網(wǎng)上流傳較廣的50道SQL訓(xùn)練,奮斗了不知道多久終于寫(xiě)完了。前18道題的難度依次遞增,從19題開(kāi)始的后半部分算是循環(huán)練習(xí)和額外function的附加練習(xí),難度恢復(fù)到普通狀態(tài)。...