2017計算機等考三級數據庫模擬練習題
2017下半年計算機等級考試時間9月23日-26日,同學們在複習過程中,練習題更是不可忽視的一部分,以下是本站小編搜索整理的一份2017計算機等考三級數據庫模擬練習題,供參考練習,希望對大家有所幫助!
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)。要查找選修 "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,實現數據檢索的語句是(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,分別稱為交互式SQL和(c )
A.提示式SQL
B.多用户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")
7.檢索學生姓名及其所選修課程的課程號和成績。正確的SELECT語句是( C)
CT ,SC.C#,E
FROMS
WHERE S.S#=SC.S#
ECT ,SC.C#,E
FROM SC
WHERE S.S#=S
CT ,SC.C#,E
FROM S,SC
WHERE S.S#:S C.S#
ECT ,SC.C#,E
FROM S,SC
8.檢索選修四門以上課程的學生總成績(不統計不及格的課程),並要求按總成績的降序捧列出來。正確的SElECT語句是( B)
CT S#,SUM(GRADE)FROM SC
WHERE GRADE >=60
CROUP BY S#
ORDER BY 2 DESC
HAVING COUNT(*) >=4
CT S#,SUM(GRADE)FROM SC
WHERE GRADE >=60
GROUP BY S#
HAVING COUNT(*) >=4
ORDER BY 2 DESC
CT S#,SUM(GRADE)FROM SC
WHERE GRADE >=60
HAVINC COUNT(*) >=4
GROUP BY S#
ORDER BY 2 DESC
CT S#,SUM(GRADE)FROM SC
WHERE GRADE >=60
ORDER BY 2 DESC
CROUP BY S#
HAVINC COUNT(*) >=4
9.若用如下的SQL語句創建一個student表:
CREATE TABLE student NO C(4)NOT NULL,
NAME C(8)NOT NULL,
SEX C(2),
AGE N(2)
可以插入到student表中的是(b )
A.(’1031’,’曾華’,男,23)
B.(’1031’,’曾華’,NULL,NULL)
C.(NULL,’曾華’,’男’,’23’)
D.(’1031’,NULL,’男’,23)
語言是(b )的語言,易學習。
A.過程化
B.非過程化
C.格式化
D.導航式