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 <11819570+zheshiyifenglibiexing@user.noreply.gitee.com>
Date: Thu, 23 Feb 2023 23:17:40 +0000
Subject: [PATCH] =?UTF-8?q?MySQL=E4=BD=9C=E4=B8=9A?=
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Signed-off-by: 李佳鹏 <11819570+zheshiyifenglibiexing@user.noreply.gitee.com>
---
 "20230223 \347\272\246\346\235\237.md" | 110 +++++++++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100644 "20230223 \347\272\246\346\235\237.md"

diff --git "a/20230223 \347\272\246\346\235\237.md" "b/20230223 \347\272\246\346\235\237.md"
new file mode 100644
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+# 第一题
+
+```sql
+ create table offices(
+officecode int,
+city varchar(30),
+address varchar(50),
+country varchar(50),
+postalcode varchar(25)
+);
+create table employees(
+empnum int(11),
+lastname varchar(50),
+firstname varchar(50),
+mobile varchar(25),
+code int,
+jobtitle varchar(50),
+birth date,
+note varchar(225),
+sex varchar(5)
+);
+ALTER table employees modify mobile int AFTER code;
+alter table employees change birth birthday int;
+ALTER table employees modify sex char(1);
+ALTER table employees drop note;
+alter table employees add favoriate_activity varchar(100) first;
+alter table employees RENAME employees_info;
+```
+
+# 第二题
+
+```sql
+create table if NOT EXISTS pet(
+name varchar(20) COMMENT '宠物名称',
+owner varchar(20) comment '宠物主人',
+species varchar(20) comment '种类',
+sex char(1) comment '性别',
+birth year comment '出生日期',
+death year comment '死亡日期'
+);
+INSERT INTO pet values('fluffy','harold','cat','f','2003','2010');
+insert into pet values('claws','gwen','cat','m','2004',null);
+insert into pet values('buffy',null,'dog','f','2009',null);
+insert into pet values('fang','benny','dog','m','2000',null);
+insert into pet values('bowser','diane','dog','m','2003','2009');
+insert into pet values('chirpy',null,'bird','f','2008',null);
+ALTER table pet add owner_birth date;
+UPDATE pet set owner='kevin' where `NAME`='claws';
+update pet set owner='duck' where death is null and species='dog';
+SELECT name,owner from  pet where owner is null;
+select name,owner,death from pet where death is not null and species='cat';
+DELETE from pet where death is not null and species='dog';
+select name,owner,species,sex,birth,death from pet;
+```
+
+# 第三题
+
+```sql
+create table department(
+depid int PRIMARY KEY,
+depname varchar(20),
+deinfo VARCHAR(50)
+);
+CREATE TABLE employee(
+empid int PRIMARY KEY,
+name VARCHAR(20),
+sex char DEFAULT '男',
+title VARCHAR(20),
+birthday date,
+depid int,
+FOREIGN KEY(depid) REFERENCES department(depid) on UPDATE CASCADE on DELETE SET null
+);
+CREATE TABLE salary(
+empid int PRIMARY KEY,
+basesalary double,
+titlesalary double,
+deduction double
+);
+
+alter table salary add FOREIGN KEY(empid) REFERENCES employee(empid) on UPDATE CASCADE on DELETE CASCADE;
+
+INSERT into department VALUES(111,'生产部',NULL),(222,'销售部',NULL),(333,'人事部','人力资源管理');
+
+INSERT INTO employee VALUES(1001,'张三','男','高级工程师','1975-1-1',111),(1002,'李四','女','助工','1985-1-1',111),(1003,'王五','男','工程师','1978-11-11',222),(1004,'张六','男','工程师','1991-1-1',222);
+
+INSERT INTO salary VALUES(1001,2200,1100,200),(1002,1200,200,NULL),(1003,2900,700,200),(1004,1950,700,150);
+```
+
+# 第四题
+
+```sql
+create table department(
+depno int(10),
+depname varchar(20),
+depnote varchar(50)
+);
+create table teacher(
+number int,
+name varchar(30),
+sex varchar(4),
+birth date,
+depno int,
+salary float,
+address varchar(100),
+FOREIGN key(dopno) REFERENCES department(depno)
+);
+insert into department VALUES(601,'软件技术系','软件技术等专业'),(602,'网络技术系','多媒体技术等专业'),(603,'艺术设计系','广告艺术设计等专业'),(604,'管理工程系','连锁经营管理专业');
+INSERT into teacher VALUES(2021,'tom','女','1970-01-10',602,4500,'四川省绵阳市'),(2002,'lucy','男','1983-12-18',601,2500,'北京市昌平区'),(2003,'mike','男','1990-06-01',604,1500,'重庆市渝中区'),(2004,'james','女','1975-05-20',602,3500,'四川省成都市'),(2005,'javk','男','1975-05-30',603,1200,'重庆市南岸区');
+```
+
-- 
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