CREATE TABLE STUDENT
(SNO VARCHAR(3) NOT NULL,
SNAME VARCHAR(4) NOT NULL,
SSEX VARCHAR(2) NOT NULL,
SBIRTHDAY DATETIME,
CLASS VARCHAR(5))ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
(SNO VARCHAR(3) NOT NULL,
SNAME VARCHAR(4) NOT NULL,
SSEX VARCHAR(2) NOT NULL,
SBIRTHDAY DATETIME,
CLASS VARCHAR(5))ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
CREATE TABLE COURSE
(CNO VARCHAR(5) NOT NULL,
CNAME VARCHAR(10) NOT NULL,
TNO VARCHAR(10) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
(CNO VARCHAR(5) NOT NULL,
CNAME VARCHAR(10) NOT NULL,
TNO VARCHAR(10) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
CREATE TABLE SCORE
(SNO VARCHAR(3) NOT NULL,
CNO VARCHAR(5) NOT NULL,
DEGREE NUMERIC(10, 1) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
(SNO VARCHAR(3) NOT NULL,
CNO VARCHAR(5) NOT NULL,
DEGREE NUMERIC(10, 1) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
CREATE TABLE TEACHER
(TNO VARCHAR(3) NOT NULL,
TNAME VARCHAR(4) NOT NULL, TSEX VARCHAR(2) NOT NULL,
TBIRTHDAY DATETIME NOT NULL, PROF VARCHAR(6),
DEPART VARCHAR(10) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
(TNO VARCHAR(3) NOT NULL,
TNAME VARCHAR(4) NOT NULL, TSEX VARCHAR(2) NOT NULL,
TBIRTHDAY DATETIME NOT NULL, PROF VARCHAR(6),
DEPART VARCHAR(10) NOT NULL)ENGINE=MyISAM AUTO_INCREMENT=348 DEFAULT CHARSET=utf8 ;;
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (108 ,'曾華'
,'男' ,1977-09-01,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明'
,'男' ,1975-10-02,95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王麗'
,'女' ,1976-01-23,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李軍'
,'男' ,1976-02-20,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳'
,'女' ,1975-02-10,95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陸君'
,'男' ,1974-06-03,95031);
,'男' ,1977-09-01,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明'
,'男' ,1975-10-02,95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王麗'
,'女' ,1976-01-23,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李軍'
,'男' ,1976-02-20,95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳'
,'女' ,1975-02-10,95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陸君'
,'男' ,1974-06-03,95031);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('3-105' ,'計算機導論',825);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系統' ,804);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('6-166' ,'數據電路' ,856);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('9-888' ,'高等數學' ,100);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系統' ,804);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('6-166' ,'數據電路' ,856);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('9-888' ,'高等數學' ,100);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (103,'3-245',86);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-245',75);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-245',68);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (103,'3-105',92);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-105',88);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-105',76);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'3-105',64);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'3-105',91);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'3-105',78);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'6-166',85);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'6-106',79);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'6-166',81);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-245',75);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-245',68);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (103,'3-105',92);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-105',88);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-105',76);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'3-105',64);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'3-105',91);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'3-105',78);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'6-166',85);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'6-106',79);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'6-166',81);
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (804,'李誠','男','1958-12-02','副教授','計算機系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (856,'張旭','男','1969-03-12','講師','電子工程系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (825,'王萍','女','1972-05-05','助教','計算機系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (831,'劉冰','女','1977-08-14','助教','電子工程系');
VALUES (804,'李誠','男','1958-12-02','副教授','計算機系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (856,'張旭','男','1969-03-12','講師','電子工程系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (825,'王萍','女','1972-05-05','助教','計算機系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (831,'劉冰','女','1977-08-14','助教','電子工程系');
題目：
1、 查詢Student表中的所有記錄的Sname、Ssex和Class列。
2、 查詢教師所有的單位即不重複的Depart列。
3、 查詢Student表的所有記錄。
4、 查詢Score表中成績在60到80之間的所有記錄。
5、 查詢Score表中成績為85，86或88的記錄。
6、 查詢Student表中「95031」班或性別為「女」的同學記錄。
7、 以Class降序查詢Student表的所有記錄。
8、 以Cno升序、Degree降序查詢Score表的所有記錄。
9、 查詢「95031」班的學生人數。
10、查詢Score表中的最高分的學生學號和課程號。
11、查詢『3-105』號課程的平均分。
12、查詢Score表中至少有5名學生選修的並以3開頭的課程的平均分數。
13、查詢最低分大於70，最高分小於90的Sno列。
14、查詢所有學生的Sname、Cno和Degree列。
15、查詢所有學生的Sno、Cname和Degree列。
16、查詢所有學生的Sname、Cname和Degree列。
17、查詢「95033」班所選課程的平均分。
18、假設使用如下命令建立了一個grade表：
create table grade(low number(3,0),upp number(3),rank char(1));
insert into grade values(90,100,』A』);
insert into grade values(80,89,』B』);
insert into grade values(70,79,』C』);
insert into grade values(60,69,』D』);
insert into grade values(0,59,』E』);
commit;
現查詢所有同學的Sno、Cno和rank列。
19、查詢選修「3-105」課程的成績高於「109」號同學成績的所有同學的記錄。
20、查詢score中選學一門以上課程的同學中分數為非最高分成績的記錄。
21、查詢成績高於學號為「109」、課程號為「3-105」的成績的所有記錄。
22、查詢和學號為108的同學同年出生的所有學生的Sno、Sname和Sbirthday列。
23、查詢「張旭「教師任課的學生成績。
24、查詢選修某課程的同學人數多於5人的教師姓名。
25、查詢95033班和95031班全體學生的記錄。
26、查詢存在有85分以上成績的課程Cno.
27、查詢出「計算機系「教師所教課程的成績表。
28、查詢「計算機系」與「電子工程系「不同職稱的教師的Tname和Prof。
29、查詢選修編號為「3-105「課程且成績至少高於選修編號為「3-245」的同學的Cno、Sno和Degree,並按Degree從高到低次序排序。
30、查詢選修編號為「3-105」且成績高於選修編號為「3-245」課程的同學的Cno、Sno和Degree.
31、查詢所有教師和同學的name、sex和birthday.
32、查詢所有「女」教師和「女」同學的name、sex和birthday.
33、查詢成績比該課程平均成績低的同學的成績表。
34、查詢所有任課教師的Tname和Depart.
35 查詢所有未講課的教師的Tname和Depart.
36、查詢至少有2名男生的班號。
37、查詢Student表中不姓「王」的同學記錄。
38、查詢Student表中每個學生的姓名和年齡。
39、查詢Student表中最大和最小的Sbirthday日期值。
40、以班號和年齡從大到小的順序查詢Student表中的全部記錄。
41、查詢「男」教師及其所上的課程。
42、查詢最高分同學的Sno、Cno和Degree列。
43、查詢和「李軍」同性別的所有同學的Sname.
44、查詢和「李軍」同性別並同班的同學Sname.
45、查詢所有選修「計算機導論」課程的「男」同學的成績表
參考答案：
1. SELECT SNAME,SSEX,CLASS FROM STUDENT;
2. SELECT DISTINCT DEPART FROM TEACHER;
3. SELECT * FROM STUDENT;
4. SELECT * FROM SCORE WHERE DEGREE BETWEEN 60 AND 80;
5.SELECT * FROM SCORE WHERE DEGREE IN (85,86,88);
6. SELECT * FROM STUDENT WHERE CLASS='95031' OR SSEX='女';
7.SELECT * FROM STUDENT ORDER BY CLASS DESC;
8.SELECT * FROM SCORE ORDER BY CNO ASC,DEGREE DESC;
9.SELECT COUNT(*) FROM STUDENT WHERE CLASS='95031';
10.SELECT SNO,CNO FROM SCORE WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE);
SELECT SNO,CNO FROM SCORE ORDER BY DEGREE DESC LIMIT 1;
11.SELECT AVG(DEGREE) FROM SCORE WHERE CNO='3-105';
12.select avg(degree),cno
from score
where cno like '3%'
group by cno
having count(sno)>= 5;
13.SELECT SNO FROM SCORE GROUP BY SNO HAVING MIN(DEGREE)>70 AND MAX(DEGREE)<90;
14.SELECT A.SNAME,B.CNO,B.DEGREE FROM STUDENT AS A JOIN SCORE AS B ON A.SNO=B.SNO;
15.SELECT A.CNAME, B.SNO,B.DEGREE FROM COURSE AS A JOIN SCORE AS B ON A.CNO=B.CNO ;
16.SELECT A.SNAME,B.CNAME,C.DEGREE FROM STUDENT A JOIN (COURSE B,SCORE C)
ON A.SNO=C.SNO AND B.CNO =C.CNO;
17.SELECT AVG(A.DEGREE) FROM SCORE A JOIN STUDENT B ON A.SNO = B.SNO WHERE B.CLASS='95033';
18.SELECT A.SNO,A.CNO,B.RANK FROM SCORE A,GRADE B WHERE A.DEGREE BETWEEN B.LOW AND B.UPP
ORDER BY RANK;
19.SELECT A.* FROM SCORE A JOIN SCORE B WHERE A.CNO='3-105' AND A.DEGREE>B.DEGREE AND
B.SNO='109' AND B.CNO='3-105';
另一解法：SELECT A.* FROM SCORE A WHERE A.CNO='3-105' AND A.DEGREE>ALL(SELECT DEGREE FROM
SCORE B WHERE B.SNO='109' AND B.CNO='3-105');
20.SELECT * FROM score s WHERE DEGREE<(SELECT MAX(DEGREE) FROM SCORE) GROUP BY SNO HAVING
COUNT(SNO)>1 ORDER BY DEGREE ;
21.見19的第二種解法
22。SELECT SNO,SNAME,SBIRTHDAY FROM STUDENT WHERE YEAR(SBIRTHDAY)=(SELECT YEAR(SBIRTHDAY)
FROM STUDENT WHERE SNO='108');
ORACLE:select x.cno,x.Sno,x.degree from score x,score y where x.degree>y.degree and
y.sno='109'and y.cno='3-105';
select cno,sno,degree from score where degree >(select degree from score where sno='109'
and cno='3-105')
23.SELECT A.SNO,A.DEGREE FROM SCORE A JOIN (TEACHER B,COURSE C)
ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.TNAME='張旭';
另一種解法：select cno,sno,degree from score where cno=(select x.cno from course x,teacher y
where x.tno=y.tno and y.tname='張旭');
根據實際EXPLAIN此SELECT語句，第一個的掃描次數要小於第二個
24.SELECT A.TNAME FROM TEACHER A JOIN (COURSE B, SCORE C) ON (A.TNO=B.TNO AND B.CNO=C.CNO)
GROUP BY C.CNO HAVING COUNT(C.CNO)>5;
另一種解法：select tname from teacher where tno in(select x.tno from course x,score y where
x.cno=y.cno group by x.tno having count(x.tno)>5);
實際測試1明顯優於2
25。select cno,sno,degree from score where cno=(select x.cno from course x,teacher y where
x.tno=y.tno and y.tname='張旭');
26。SELECT CNO FROM SCORE GROUP BY CNO HAVING MAX(DEGREE)>85;
另一種解法：select distinct cno from score where degree in (select degree from score where
degree>85);
27。SELECT A.* FROM SCORE A JOIN (TEACHER B,COURSE C) ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.DEPART='計算機系';
另一種解法：SELECT * from score where cno in (select a.cno from course a join teacher b on
a.tno=b.tno and b.depart='計算機系');
此時2略好於1，在多連接的境況下性能會迅速下降
28。select tname,prof from teacher where depart='計算機系' and prof not in (select prof from
teacher where depart='電子工程系');
29。SELECT * FROM SCORE WHERE DEGREE>ANY(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER
BY DEGREE DESC;
30。SELECT * FROM SCORE WHERE DEGREE>ALL(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER
BY DEGREE DESC;
31.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER;
32.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT WHERE SSEX='女'
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER WHERE TSEX='女';
33.SELECT A.* FROM SCORE A WHERE DEGREE<(SELECT AVG(DEGREE) FROM SCORE B WHERE A.CNO=B.CNO);
須注意********此題
34。解法一：SELECT A.TNAME,A.DEPART FROM TEACHER A JOIN COURSE B ON A.TNO=B.TNO;
解法二：select tname,depart from teacher a where exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO IN (SELECT TNO FROM COURSE);
實際分析，第一種揭發貌似更好，至少掃描次數最少。
35.解法一：SELECT TNAME,DEPART FROM TEACHER A LEFT JOIN COURSE B USING(TNO) WHERE ISNUL
(B.tno);
解法二：select tname,depart from teacher a where not exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO NOT IN (SELECT TNO FROM COURSE);
NOT IN的方法效率最差，其餘兩種差不多
36.SELECT CLASS FROM STUDENT A WHERE SSEX='男' GROUP BY CLASS HAVING COUNT(SSEX)>1;
37.SELECT * FROM STUDENT A WHERE SNAME not like '王%';
38.SELECT SNAME,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT;
39.select sname,sbirthday as THEMAX from student where sbirthday =(select min(SBIRTHDAY)
from student)
union
select sname,sbirthday as THEMIN from student where sbirthday =(select max(SBIRTHDAY) from
student);
40.SELECT CLASS,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT ORDER BY CLASS DESC,AGE
DESC;
41.SELECT A.TNAME,B.CNAME FROM TEACHER A JOIN COURSE B USING(TNO) WHERE A.TSEX='男';
42.SELECT A.* FROM SCORE A WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE B );
43.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李軍');
44.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李軍' )
AND CLASS=(SELECT CLASS FROM STUDENT C WHERE c.SNAME='李軍');
45.解法一：SELECT A.* FROM SCORE A JOIN (STUDENT B,COURSE C) USING(sno,CNO) WHERE B.SSEX='男
' AND C.CNAME='計算機導論';
解法二：select * from score where sno in(select sno from student where
ssex='男') and cno=(select cno from course
where cname='計算機導論');
1、 查詢Student表中的所有記錄的Sname、Ssex和Class列。
2、 查詢教師所有的單位即不重複的Depart列。
3、 查詢Student表的所有記錄。
4、 查詢Score表中成績在60到80之間的所有記錄。
5、 查詢Score表中成績為85，86或88的記錄。
6、 查詢Student表中「95031」班或性別為「女」的同學記錄。
7、 以Class降序查詢Student表的所有記錄。
8、 以Cno升序、Degree降序查詢Score表的所有記錄。
9、 查詢「95031」班的學生人數。
10、查詢Score表中的最高分的學生學號和課程號。
11、查詢『3-105』號課程的平均分。
12、查詢Score表中至少有5名學生選修的並以3開頭的課程的平均分數。
13、查詢最低分大於70，最高分小於90的Sno列。
14、查詢所有學生的Sname、Cno和Degree列。
15、查詢所有學生的Sno、Cname和Degree列。
16、查詢所有學生的Sname、Cname和Degree列。
17、查詢「95033」班所選課程的平均分。
18、假設使用如下命令建立了一個grade表：
create table grade(low number(3,0),upp number(3),rank char(1));
insert into grade values(90,100,』A』);
insert into grade values(80,89,』B』);
insert into grade values(70,79,』C』);
insert into grade values(60,69,』D』);
insert into grade values(0,59,』E』);
commit;
現查詢所有同學的Sno、Cno和rank列。
19、查詢選修「3-105」課程的成績高於「109」號同學成績的所有同學的記錄。
20、查詢score中選學一門以上課程的同學中分數為非最高分成績的記錄。
21、查詢成績高於學號為「109」、課程號為「3-105」的成績的所有記錄。
22、查詢和學號為108的同學同年出生的所有學生的Sno、Sname和Sbirthday列。
23、查詢「張旭「教師任課的學生成績。
24、查詢選修某課程的同學人數多於5人的教師姓名。
25、查詢95033班和95031班全體學生的記錄。
26、查詢存在有85分以上成績的課程Cno.
27、查詢出「計算機系「教師所教課程的成績表。
28、查詢「計算機系」與「電子工程系「不同職稱的教師的Tname和Prof。
29、查詢選修編號為「3-105「課程且成績至少高於選修編號為「3-245」的同學的Cno、Sno和Degree,並按Degree從高到低次序排序。
30、查詢選修編號為「3-105」且成績高於選修編號為「3-245」課程的同學的Cno、Sno和Degree.
31、查詢所有教師和同學的name、sex和birthday.
32、查詢所有「女」教師和「女」同學的name、sex和birthday.
33、查詢成績比該課程平均成績低的同學的成績表。
34、查詢所有任課教師的Tname和Depart.
35 查詢所有未講課的教師的Tname和Depart.
36、查詢至少有2名男生的班號。
37、查詢Student表中不姓「王」的同學記錄。
38、查詢Student表中每個學生的姓名和年齡。
39、查詢Student表中最大和最小的Sbirthday日期值。
40、以班號和年齡從大到小的順序查詢Student表中的全部記錄。
41、查詢「男」教師及其所上的課程。
42、查詢最高分同學的Sno、Cno和Degree列。
43、查詢和「李軍」同性別的所有同學的Sname.
44、查詢和「李軍」同性別並同班的同學Sname.
45、查詢所有選修「計算機導論」課程的「男」同學的成績表
參考答案：
1. SELECT SNAME,SSEX,CLASS FROM STUDENT;
2. SELECT DISTINCT DEPART FROM TEACHER;
3. SELECT * FROM STUDENT;
4. SELECT * FROM SCORE WHERE DEGREE BETWEEN 60 AND 80;
5.SELECT * FROM SCORE WHERE DEGREE IN (85,86,88);
6. SELECT * FROM STUDENT WHERE CLASS='95031' OR SSEX='女';
7.SELECT * FROM STUDENT ORDER BY CLASS DESC;
8.SELECT * FROM SCORE ORDER BY CNO ASC,DEGREE DESC;
9.SELECT COUNT(*) FROM STUDENT WHERE CLASS='95031';
10.SELECT SNO,CNO FROM SCORE WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE);
SELECT SNO,CNO FROM SCORE ORDER BY DEGREE DESC LIMIT 1;
11.SELECT AVG(DEGREE) FROM SCORE WHERE CNO='3-105';
12.select avg(degree),cno
from score
where cno like '3%'
group by cno
having count(sno)>= 5;
13.SELECT SNO FROM SCORE GROUP BY SNO HAVING MIN(DEGREE)>70 AND MAX(DEGREE)<90;
14.SELECT A.SNAME,B.CNO,B.DEGREE FROM STUDENT AS A JOIN SCORE AS B ON A.SNO=B.SNO;
15.SELECT A.CNAME, B.SNO,B.DEGREE FROM COURSE AS A JOIN SCORE AS B ON A.CNO=B.CNO ;
16.SELECT A.SNAME,B.CNAME,C.DEGREE FROM STUDENT A JOIN (COURSE B,SCORE C)
ON A.SNO=C.SNO AND B.CNO =C.CNO;
17.SELECT AVG(A.DEGREE) FROM SCORE A JOIN STUDENT B ON A.SNO = B.SNO WHERE B.CLASS='95033';
18.SELECT A.SNO,A.CNO,B.RANK FROM SCORE A,GRADE B WHERE A.DEGREE BETWEEN B.LOW AND B.UPP
ORDER BY RANK;
19.SELECT A.* FROM SCORE A JOIN SCORE B WHERE A.CNO='3-105' AND A.DEGREE>B.DEGREE AND
B.SNO='109' AND B.CNO='3-105';
另一解法：SELECT A.* FROM SCORE A WHERE A.CNO='3-105' AND A.DEGREE>ALL(SELECT DEGREE FROM
SCORE B WHERE B.SNO='109' AND B.CNO='3-105');
20.SELECT * FROM score s WHERE DEGREE<(SELECT MAX(DEGREE) FROM SCORE) GROUP BY SNO HAVING
COUNT(SNO)>1 ORDER BY DEGREE ;
21.見19的第二種解法
22。SELECT SNO,SNAME,SBIRTHDAY FROM STUDENT WHERE YEAR(SBIRTHDAY)=(SELECT YEAR(SBIRTHDAY)
FROM STUDENT WHERE SNO='108');
ORACLE:select x.cno,x.Sno,x.degree from score x,score y where x.degree>y.degree and
y.sno='109'and y.cno='3-105';
select cno,sno,degree from score where degree >(select degree from score where sno='109'
and cno='3-105')
23.SELECT A.SNO,A.DEGREE FROM SCORE A JOIN (TEACHER B,COURSE C)
ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.TNAME='張旭';
另一種解法：select cno,sno,degree from score where cno=(select x.cno from course x,teacher y
where x.tno=y.tno and y.tname='張旭');
根據實際EXPLAIN此SELECT語句，第一個的掃描次數要小於第二個
24.SELECT A.TNAME FROM TEACHER A JOIN (COURSE B, SCORE C) ON (A.TNO=B.TNO AND B.CNO=C.CNO)
GROUP BY C.CNO HAVING COUNT(C.CNO)>5;
另一種解法：select tname from teacher where tno in(select x.tno from course x,score y where
x.cno=y.cno group by x.tno having count(x.tno)>5);
實際測試1明顯優於2
25。select cno,sno,degree from score where cno=(select x.cno from course x,teacher y where
x.tno=y.tno and y.tname='張旭');
26。SELECT CNO FROM SCORE GROUP BY CNO HAVING MAX(DEGREE)>85;
另一種解法：select distinct cno from score where degree in (select degree from score where
degree>85);
27。SELECT A.* FROM SCORE A JOIN (TEACHER B,COURSE C) ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.DEPART='計算機系';
另一種解法：SELECT * from score where cno in (select a.cno from course a join teacher b on
a.tno=b.tno and b.depart='計算機系');
此時2略好於1，在多連接的境況下性能會迅速下降
28。select tname,prof from teacher where depart='計算機系' and prof not in (select prof from
teacher where depart='電子工程系');
29。SELECT * FROM SCORE WHERE DEGREE>ANY(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER
BY DEGREE DESC;
30。SELECT * FROM SCORE WHERE DEGREE>ALL(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER
BY DEGREE DESC;
31.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER;
32.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT WHERE SSEX='女'
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER WHERE TSEX='女';
33.SELECT A.* FROM SCORE A WHERE DEGREE<(SELECT AVG(DEGREE) FROM SCORE B WHERE A.CNO=B.CNO);
須注意********此題
34。解法一：SELECT A.TNAME,A.DEPART FROM TEACHER A JOIN COURSE B ON A.TNO=B.TNO;
解法二：select tname,depart from teacher a where exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO IN (SELECT TNO FROM COURSE);
實際分析，第一種揭發貌似更好，至少掃描次數最少。
35.解法一：SELECT TNAME,DEPART FROM TEACHER A LEFT JOIN COURSE B USING(TNO) WHERE ISNUL
(B.tno);
解法二：select tname,depart from teacher a where not exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO NOT IN (SELECT TNO FROM COURSE);
NOT IN的方法效率最差，其餘兩種差不多
36.SELECT CLASS FROM STUDENT A WHERE SSEX='男' GROUP BY CLASS HAVING COUNT(SSEX)>1;
37.SELECT * FROM STUDENT A WHERE SNAME not like '王%';
38.SELECT SNAME,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT;
39.select sname,sbirthday as THEMAX from student where sbirthday =(select min(SBIRTHDAY)
from student)
union
select sname,sbirthday as THEMIN from student where sbirthday =(select max(SBIRTHDAY) from
student);
40.SELECT CLASS,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT ORDER BY CLASS DESC,AGE
DESC;
41.SELECT A.TNAME,B.CNAME FROM TEACHER A JOIN COURSE B USING(TNO) WHERE A.TSEX='男';
42.SELECT A.* FROM SCORE A WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE B );
43.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李軍');
44.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李軍' )
AND CLASS=(SELECT CLASS FROM STUDENT C WHERE c.SNAME='李軍');
45.解法一：SELECT A.* FROM SCORE A JOIN (STUDENT B,COURSE C) USING(sno,CNO) WHERE B.SSEX='男
' AND C.CNAME='計算機導論';
解法二：select * from score where sno in(select sno from student where
ssex='男') and cno=(select cno from course
where cname='計算機導論');
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