以下题目用到工程供应数据库关系模式:
供应商(供应商号,供应商名,城市)
S(Sno,Sname,City)
零件(零件号,零件名,零件颜色)
P(Pno,Pname,Color)
工程(工程号,工程名 )
J(Jno,Jname)
供应(供应商号,零件号,工程号,供应数量)
SPJ(Sno,Pno,Jno,Qty)
1. 求供应工程号‘J1’零件的供应商名SNAME。(用IN 子查询)
结果应该是S-A
SELECT SNAME
FROM S
WHERE SNO IN
(
SELECT SNO
FROM SPJ
WHERE JNO=‘J1‘
)
2. 求供应工程号‘J1’零件的供应商名SNAME。(用连接, 查询结果要消除重复)
结果应该是S-A
SELECT DISTINCT SNAME
FROM S,SPJ
WHERE S.SNO=SPJ.SNO AND JNO=‘J1‘
3. 求供应工程号‘J1’零件的供应商名SNAME。(EXISTS子查询)
结果应该是S-A
SELECT SNAME
FROM S
WHERE EXISTS
(
SELECT *
FROM SPJ
WHERE S.SNO=SPJ.SNO AND JNO=‘J1‘
)
4求没有供应过零件的供应商名。(NOT IN)
结果应是S-C, S-D
SELECT SNAME
FROM S
WHERE SNO NOT IN
(
SELECT SNO
FROM SPJ
WHERE QTY!=0
)
5求没有供应过零件的供应商名。(NOT EXISTS)
结果应是S-C, S-D
SELECT SNAME
FROM S
WHERE NOT EXISTS
(
SELECT *
FROM SPJ
WHERE S.SNO=SPJ.SNO AND QTY!=0
)
6. 求使用所有零件的工程名JNAME。
(查询工程中的工程名, 条件是不存在这样的零件, 该工程不用)
结果应该是J-A
SELECT JNAME
FROM J
WHERE NOT EXISTS
(
SELECT *
FROM P
WHERE NOT EXISTS
(
SELECT *
FROM SPJ
WHERE JNO=J.JNO AND PNO=P.PNO
)
)
7.求至少用了 工程号‘J2’ 工程所使用所有零件的工程名JNAME。
(从J中查询JNAME, 条件是不存在这样的零件: J2使用并且该工程不用)
结果应该是J-A, J-B
SELECT JNAME
FROM J
WHERE NOT EXISTS
(
SELECT *
FROM P
WHERE EXISTS
(
SELECT *
FROM SPJ
WHERE JNO=‘J2‘ AND PNO=P.PNO
)
AND
NOT EXISTS
(
SELECT *
FROM SPJ
WHERE JNO=J.JNO AND PNO=P.PNO
)
)
8. 求供应了供应商号为‘S2’所供应所有零件的供应商名SNAME
(查询供应商名,条件是不存在这样的零件: S2供应并且该供应商不供应)
SELECT SNAME FROM S WHERE NOT EXISTS ( SELECT * FROM P WHERE EXISTS( SELECT * FROM SPJ WHERE SPJ.SNO=‘S2‘ AND SPJ.PNO=P.PNO ) AND NOT EXISTS( SELECT * FROM SPJ WHERE SPJ.SNO=S.SNO AND SPJ.PNO=P.PNO ) )
9. 查询供应了所有工程的供应商名。
(查询供应商名,条件是不存在这样的工程, 该供应商不供应)
SELECT SNAME FROM S WHERE NOT EXISTS ( SELECT * FROM J WHERE NOT EXISTS ( SELECT * FROM SPJ WHERE S.SNO=SNO AND J.JNO=JNO ) )
10. 查询没有使用北京供应商供应的’红’色零件的工程名(NOT IN)
结果应该是J-A, J-B,J-C
SELECT JNAME
FROM J
WHERE JNO NOT IN
(
SELECT JNO
FROM SPJ,S,P
WHERE SPJ.SNO=S.SNO AND SPJ.PNO=P.PNO
AND CITY=‘北京‘ AND COLOR =‘红‘
)
11. 查询供应商号,供应商名,工程号,零件号,数量。包括未供应过零件的供应商。
SELECT S.SNO,SNAME,SPJ.JNO,SPJ.PNO,QTY
FROM S,SPJ
WHERE S.SNO *=SPJ.SNO
12 查询供应过颜色为’黑’的零件的供应商名
SELECT SNAME
FROM S,P,SPJ
WHERE S.SNO =SPJ.SNO AND P.PNO=SPJ.PNO AND COLOR=‘黑‘
13查询供应商号,工程号, 供应零件数量合计
SELECT SNO,JNO,COUNT(QTY)
FROM SPJ
GROUP BY SNO,JNO
14,查询工程号,工程名,供应的次数,供应的零件数量合计
SELECT J.JNO,JNAME,COUNT(*),SUM(QTY) FROM J,SPJ WHERE J.JNO=SPJ.JNO GROUP BY J.JNO,JNAME
15查询与供应商名‘S-C’同城市的供应商名
SELECT SNAME
FROM S
WHERE CITY=
(
SELECT CITY
FROM S
WHERE SNAME=‘S-C‘
)
16查询供应过>=3次的供应商名
SELECT SNAME
FROM S
WHERE SNO IN
(
SELECT SNO
FROM SPJ
GROUP BY SNO
HAVING COUNT(*)>=3
)
17. 查询供应次数大于S2供应次数的供应商号
SELECT SNO FROM SPJ GROUP BY SNO HAVING COUNT(*)> ( SELECT COUNT(*) FROM SPJ WHERE SNO=‘S2‘ )
18查询供应给工程号’J2’ 零件数>=10的供应商名
SELECT SNAME
FROM S
WHERE SNO IN
(
SELECT SNO
FROM SPJ
WHERE JNO=‘J2‘
GROUP BY SNO
HAVING SUM(QTY)>=10
)
原文:https://www.cnblogs.com/wkfvawl/p/10845615.html