考前多做些習題,能夠更好地掌握知識,下面小編為大家帶來了計算機等級考試三級資料庫考前選擇題練習,歡迎大家閱讀!
計算機等級考試三級資料庫考前選擇題練習1.假定學生關係是S(S#,SNAME,SEX,AGE),課程關係是C(C#,CNAME,TEACHER),學生選課關係是SC(S#,C#,GRADE)。要查詢選修 "COMPUTER"課程的"女"學生姓名,將涉及到關係(d )
A.S
, C
C.S,SC
D.S,C,SC
語言中,實現資料檢索的語句是(a )
CT
RT
TE
TE
3.下列SQL語句中,修改表結構的是(a )
R
TE
TE
RT
語言具有兩種使用方式,分別稱為互動式SQL和(c )
A.提示式SQL
B.多使用者SQL
C.嵌入式SQL
D.解釋式SQL
5.檢索所有比 "王華"年齡大的學生姓名、年齡和性別。正確的`SELECT語句是(a )
CT SN,AGE,SEX FROM S
SHERE AGE > (SELECT AGE FROM S)
WHERE SN=’王華’)
CT SN,AGE,SEX
FROM S
WHERE SN=’王華’
CT SN,ACE,SEX FROM S
WHERE AGE >(SELECT ACE
WHERE SN=’王華’)
CT SN,ACE,SEX FROM S
WHERE ACE >王華 AGE
6.檢索選修課程"C2"的學生中成績最高的學生的學號。正確的SeLECT的語句是(d )
CT S# FORM SC
WHERE C#= "C2" AND GRADE> =(SELECT GRADE FORM SC)
WHERE C#= "C2")
CT S#FORM SC
WHERE C#= "C2" AND GRADE IN(SELECT CRADE FORM SC)
WHERE C#= "C2"
CT S# FORM SC
WHERE C#= "C2" AND GRADE NOT IN(SELECT GRADE FORM SC
WHERE C#= "C2"
CT S# FORM SC
WHERE C#= "C2" AND CRANDE> =ALL(SELECT GRADE FORM SC
WHERE C#= "C2")