123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235 |
- # 创建部门表
- CREATE TABLE dept(
- did INT PRIMARY KEY AUTO_INCREMENT,
- dname VARCHAR(20)
- );
- # 创建员工表
- CREATE TABLE emp (
- id INT PRIMARY KEY AUTO_INCREMENT,
- NAME VARCHAR(10),
- gender CHAR(1), -- 性别
- salary DOUBLE, -- 工资
- join_date DATE, -- 入职日期
- dep_id INT,
- FOREIGN KEY (dep_id) REFERENCES dept(did) -- 外键,关联部门表(部门表的主键)
- );
- -- 添加部门数据
- INSERT INTO dept (dNAME) VALUES ('研发部'),('市场部'),('财务部'),('销售部');
- -- 添加员工数据
- INSERT INTO emp(NAME,gender,salary,join_date,dep_id) VALUES
- ('孙悟空','男',7200,'2013-02-24',1),
- ('猪八戒','男',3600,'2010-12-02',2),
- ('唐僧','男',9000,'2008-08-08',2),
- ('白骨精','女',5000,'2015-10-07',3),
- ('蜘蛛精','女',4500,'2011-03-14',1),
- ('小白龙','男',2500,'2011-02-14',null);
- # 链接查询
- # 内连接 获取交集
- select * from emp,dept; # 笛卡尔积
- # 隐式查询 99标准
- select * from emp e,dept d where e.dep_id = d.did;
- # 显示查询 92
- # 用 join连表 用 on 添加条件
- select * from emp e join dept d on e.dep_id = d.did;
- # 单独获取数据
- # 获取人员的部门名称
- select e.*,d.dname from emp e join dept d on e.dep_id = d.did;
- -- 获取人员名称和对应部门名称
- select e.NAME ,dname from dept inner join emp e on dept.did = e.dep_id;
- -- 获取 20150101之后入职的人员名称和对应部门名称
- select e.NAME ,dname from dept inner join emp e on dept.did = e.dep_id where e.join_date > '2012-12-01';
- -- 获取 薪资大于5000的员工人员名称和对应部门名称
- select
- e.NAME ,dname
- from
- dept inner join emp e
- on
- dept.did = e.dep_id
- where
- e.salary > 5000;
- # 外连接
- # 左右外链接
- # 查询emp表所有数据和对应的部门信息(左外连接)
- select e.*,d.dname from emp e left join dept d on d.did = e.dep_id;
- # 查询dept表所有数据和对应的员工信息(右外连接)
- select d.*,e.* from emp e right join dept d on d.did = e.dep_id;
- # 子查询
- # 需求: 查询工资大于孙悟空的人员.
- #
- # - 孙悟空的工资
- select salary from emp where NAME = '孙悟空';
- # - 大于 孙悟空工资的人
- select * from emp
- where salary > (
- select salary from emp where NAME = '孙悟空'
- );
- #子查询练习
- # 查询 '财务部' 和 '市场部' 所有的员工信息
- # 市场和财务的id
- select did from dept where dname = '财务部' or dname = '市场部';
- # 查询员工 = 上面条件
- select * from emp where emp.id in(
- select did from dept where dname = '财务部' or dname = '市场部'
- );
- # 查询入职日期是 '2011-11-11' 之后的员工信息和部门信息
- # 用外连接 子查询虚拟表
- select *from emp e where e.join_date > '2011-11-11';
- #
- select *
- from (select *from emp e where e.join_date > '2011-11-11') e join dept d on d.did = e.dep_id;
- # 插入数据
- DROP TABLE IF EXISTS emp;
- DROP TABLE IF EXISTS dept;
- DROP TABLE IF EXISTS job;
- DROP TABLE IF EXISTS salarygrade;
- -- 部门表
- CREATE TABLE dept (
- did INT PRIMARY KEY PRIMARY KEY, -- 部门id
- dname VARCHAR(50), -- 部门名称
- loc VARCHAR(50) -- 部门所在地
- );
- -- 职务表,职务名称,职务描述
- CREATE TABLE job (
- id INT PRIMARY KEY,
- jname VARCHAR(20),
- description VARCHAR(50)
- );
- -- 员工表
- CREATE TABLE emp (
- id INT PRIMARY KEY, -- 员工id
- ename VARCHAR(50), -- 员工姓名
- job_id INT, -- 职务id
- mgr INT , -- 上级领导
- joindate DATE, -- 入职日期
- salary DECIMAL(7,2), -- 工资
- bonus DECIMAL(7,2), -- 奖金
- dept_id INT, -- 所在部门编号
- CONSTRAINT emp_jobid_ref_job_id_fk FOREIGN KEY (job_id) REFERENCES job (id),
- CONSTRAINT emp_deptid_ref_dept_id_fk FOREIGN KEY (dept_id) REFERENCES dept (did)
- );
- -- 工资等级表
- CREATE TABLE salarygrade (
- grade INT PRIMARY KEY, -- 级别
- losalary INT, -- 最低工资
- hisalary INT -- 最高工资
- );
- -- 添加4个部门
- INSERT INTO dept(did,dname,loc) VALUES
- (10,'教研部','北京'),
- (20,'学工部','上海'),
- (30,'销售部','广州'),
- (40,'财务部','深圳');
- -- 添加4个职务
- INSERT INTO job (id, jname, description) VALUES
- (1, '董事长', '管理整个公司,接单'),
- (2, '经理', '管理部门员工'),
- (3, '销售员', '向客人推销产品'),
- (4, '文员', '使用办公软件');
- -- 添加员工
- INSERT INTO emp(id,ename,job_id,mgr,joindate,salary,bonus,dept_id) VALUES
- (1001,'孙悟空',4,1004,'2000-12-17','8000.00',NULL,20),
- (1002,'卢俊义',3,1006,'2001-02-20','16000.00','3000.00',30),
- (1003,'林冲',3,1006,'2001-02-22','12500.00','5000.00',30),
- (1004,'唐僧',2,1009,'2001-04-02','29750.00',NULL,20),
- (1005,'李逵',4,1006,'2001-09-28','12500.00','14000.00',30),
- (1006,'宋江',2,1009,'2001-05-01','28500.00',NULL,30),
- (1007,'刘备',2,1009,'2001-09-01','24500.00',NULL,10),
- (1008,'猪八戒',4,1004,'2007-04-19','30000.00',NULL,20),
- (1009,'罗贯中',1,NULL,'2001-11-17','50000.00',NULL,10),
- (1010,'吴用',3,1006,'2001-09-08','15000.00','0.00',30),
- (1011,'沙僧',4,1004,'2007-05-23','11000.00',NULL,20),
- (1012,'李逵',4,1006,'2001-12-03','9500.00',NULL,30),
- (1013,'小白龙',4,1004,'2001-12-03','30000.00',NULL,20),
- (1014,'关羽',4,1007,'2002-01-23','13000.00',NULL,10);
- -- 添加5个工资等级
- INSERT INTO salarygrade(grade,losalary,hisalary) VALUES
- (1,7000,12000),
- (2,12010,14000),
- (3,14010,20000),
- (4,20010,30000),
- (5,30010,99990);
- -- 练习
- # 查询员工编号,员工姓名,工资,职务名称,职务描述
- select
- e.id,e.ename , e.salary , j.jname ,j.description
- from emp e inner join job j on e.job_id = j.id;
- # 查询员工编号,员工姓名,工资,职务名称,职务描述,部门名称,部门位置
- select
- e.id,e.ename , e.salary , j.jname ,j.description , d.dname,d.loc
- from
- emp e inner join
- job j join dept d
- on e.dept_id = d.did and e.job_id = j.id;
- # 查询员工姓名,工资,工资等级
- select e.ename ,e.salary , s.grade
- from emp e join salarygrade s on e.salary between s.losalary and s.hisalary;
- # 查询最高工资和最低工资的员工信息
- select MAX(salary) from emp;
- select MIN(salary) from emp;
- select * from emp where salary in ((select MAX(salary) from emp),(select MIN(salary) from emp));
- select * from emp where salary in (
- (select salary from emp order by salary desc limit 1),
- (select MIN(salary) from emp));
- # 查询出部门编号、部门名称、部门位置、部门人数
- select d.did,d.dname,d.loc,count(*) from dept d inner join emp e on d.did = e.dept_id group by d.did;
- select d.did,d.dname,d.loc,count(e.dept_id) from dept d left join emp e on d.did = e.dept_id group by d.did
- # 查看事务
- select @@autocommit;
- # set 设置 0 手动提交事务
- set @@autocommit = 0;
- # 修改数据
- # 修改person内容
- update person set name = 'ls' where id = 1;
- commit ;
- # 后面 jdbc mybatis 事务 spring 事务
|