task1/README.md

task1

CREATE DATABASE dg_mysql;

SHOW DATABASES;

USE dg_mysql;

##分别创建s、p、j和spj数据表 CREATE TABLE s( sno CHAR(2), sname VARCHAR(10), STATUS INT, city VARCHAR(10) ); CREATE TABLE p( pno CHAR(2), pname VARCHAR(10), color CHAR(1), weight INT ); CREATE TABLE j( jno CHAR(2), jname VARCHAR(10), city VARCHAR(10) ); CREATE TABLE spj( sno CHAR(2), pno CHAR(2), jno CHAR(2), qty INT );

##查看s、p、j和spj数据表的详细结构 DESCRIBE s; DESCRIBE p; DESCRIBE j; DESCRIBE spj;

##插入s表数据 INSERT INTO s VALUES ('S1','精益',20,'天津'), ('S2','盛锡',10,'北京'), ('S3','东方红',30,'北京'), ('S4','丰泰盛',20,'天津'), ('S5','为民',30,'上海');

##插入p表数据 INSERT INTO p VALUES ('P1','螺母','红',12), ('P2','螺栓','绿',17), ('P3','螺丝刀','蓝',14), ('P4','螺丝刀','红',14), ('P5','凸轮','蓝',40), ('P6','齿轮','红',30);

##插入j表数据 INSERT INTO j VALUES ('J1','三建','北京'), ('J2','一汽','长春'), ('J3','弹簧厂','天津'), ('J4','造船厂','天津'), ('J5','机车厂','唐山'), ('J6','无线电厂','常州'), ('J7','半导体厂','南京');

##-插入spj表数据 INSERT INTO spj VALUES ('S1','P1','J1',200), ('S1','P1','J3',100), ('S1','P1','J4',700), ('S1','P2','J2',100), ('S2','P3','J1',400), ('S2','P3','J2',200), ('S2','P3','J4',500), ('S2','P3','J5',400), ('S2','P5','J1',400), ('S2','P5','J2',100), ('S3','P1','J1',200), ('S3','P3','J1',200), ('S4','P5','J1',100), ('S4','P6','J3',300), ('S4','P6','J4',200), ('S5','P2','J4',100), ('S5','P3','J1',200), ('S5','P6','J2',200), ('S5','P6','J4',500);

##分别查询s、p、j和spj表的所有数据 SELECT* FROM s; SELECT* FROM p; SELECT* FROM j; SELECT* FROM spj;

##1. 查询所有供应商的姓名和所在城市（按供应商姓名升序排列）。

SELECT sname,city FROM s ORDER BY sname ASC;

##2. 查询所有零件的名称、颜色、重量（按零件名称升序排列）。 SELECT pname,color,weight FROM p ORDER BY pname ASC;

##1. 查询供应工程J1零件的供应商号码(去除重复，按供应商号码升序排列)。 SELECT DISTINCT sno FROM j NATURAL JOIN spj WHERE jno='J1' ORDER BY sno ASC; SELECT DISTINCT sno FROM spj WHERE jno='J1' ORDER BY sno ASC;

##2. 查询供应工程J1零件P1的供应商号码（按供应商号码升序排列）。 SELECT sno FROM spj WHERE jno='J1'AND pno='P1' ORDER BY sno ASC;

##3. 查询使用供应商S1所供应零件的工程号码（按工程号码升序排列）。 SELECT jno FROM spj WHERE sno='S1' ORDER BY jno ASC;

##1. 查询工程项目J2使用的各种零件的名称及其数量（按零件名称升序排列）。 SELECT pname,qty FROM spj NATURAL JOIN p WHERE jno='J2' ORDER BY pname ASC;

##2. 查询上海厂商供应的所有零件号码（去除重复，按零件号码升序排列）。 SELECT DISTINCT pno FROM s NATURAL JOIN spj WHERE city='上海' ORDER BY pno ASC;

##3. 查询使用上海产的零件的工程名称（按工程名称升序排列,去除重复数据）。 SELECT DISTINCT jname FROM j INNER JOIN spj ON j.jno=spj.jno INNER JOIN s ON spj.sno=s.sno WHERE s.city='上海' ORDER BY jname ASC;

##1. 查询供应工程J1零件为红色的供应商号码（按供应商号码升序排列）。 SELECT sno FROM p NATURAL JOIN spj WHERE jno='J1'AND color='红' ORDER BY sno ASC;

##2. 查询没有使用天津供应商生产的红色零件的工程号码（去除重复数据，按工程号码升序排列）。 SELECT DISTINCT jno FROM j WHERE jno NOT IN( SELECT jno FROM s NATURAL JOIN spj NATURAL JOIN p WHERE s.city='天津'AND color='红') ORDER BY jno ASC;

##子查询 SELECT DISTINCT jno FROM j WHERE jno NOT IN( SELECT jno FROM spj WHERE sno IN (SELECT sno FROM s WHERE city='天津') AND pno IN(SELECT pno FROM p WHERE color='红'));

##not exists SELECT DISTINCT jno FROM j WHERE NOT EXISTS( SELECT jno FROM spj NATURAL JOIN p NATURAL JOIN s WHERE city='天津'AND color='红'AND j.jno=jno) ORDER BY jno ASC;

##1. 把全部红色零件的颜色改成蓝色。 UPDATE p SET color='蓝' WHERE color='红';

##2. 由S5供给J4的零件P6改为由S3供应。 UPDATE spj SET sno='S3' WHERE sno='S5'AND jno='J4'AND pno='P6';

##3. 从供应商关系中删除供应商号是S2的记录，并从供应情况关系中删除相应的记录。 DELETE FROM s WHERE sno='S2'; DELETE FROM spj WHERE sno='s2';

##4. 请将(S2，J6，P4，200)插入供应情况关系表。 INSERT INTO spj(sno,jno,pno,qty)VALUES('S2','J6','P4',200);

##1. 请为“三建”工程项目建立一个供应情况的视图(v_spj)，包括供应商代码(SNO)、零件代码(PNO)、供应数量(QTY)。 CREATE VIEW v_spj AS SELECT sno,pno,qty FROM spj WHERE jno IN( SELECT jno FROM j WHERE jname='三建' );

##(1) 查询“三建”工程项目使用的各种零件代码及其总数量(total) SELECT pno,SUM(qty) AS total FROM v_spj GROUP BY pno;

##(2) 查询供应商S1的供应情况。 SELECT* FROM v_spj WHERE sno='S1';

1.在spj表定义索引IDX_SPJ，包括（sno,pno,jno）。

CREATE INDEX IDX_SPJ ON spj(sno,pno,jno);

2. 查看spj表索引定义。

SHOW INDEX FROM spj; SELECT* FROM s; SELECT* FROM p; SELECT* FROM j; SELECT* FROM spj;