day03.sql 7.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235
  1. # 创建部门表
  2. CREATE TABLE dept(
  3. did INT PRIMARY KEY AUTO_INCREMENT,
  4. dname VARCHAR(20)
  5. );
  6. # 创建员工表
  7. CREATE TABLE emp (
  8. id INT PRIMARY KEY AUTO_INCREMENT,
  9. NAME VARCHAR(10),
  10. gender CHAR(1), -- 性别
  11. salary DOUBLE, -- 工资
  12. join_date DATE, -- 入职日期
  13. dep_id INT,
  14. FOREIGN KEY (dep_id) REFERENCES dept(did) -- 外键,关联部门表(部门表的主键)
  15. );
  16. -- 添加部门数据
  17. INSERT INTO dept (dNAME) VALUES ('研发部'),('市场部'),('财务部'),('销售部');
  18. -- 添加员工数据
  19. INSERT INTO emp(NAME,gender,salary,join_date,dep_id) VALUES
  20. ('孙悟空','男',7200,'2013-02-24',1),
  21. ('猪八戒','男',3600,'2010-12-02',2),
  22. ('唐僧','男',9000,'2008-08-08',2),
  23. ('白骨精','女',5000,'2015-10-07',3),
  24. ('蜘蛛精','女',4500,'2011-03-14',1),
  25. ('小白龙','男',2500,'2011-02-14',null);
  26. # 链接查询
  27. # 内连接 获取交集
  28. select * from emp,dept; # 笛卡尔积
  29. # 隐式查询 99标准
  30. select * from emp e,dept d where e.dep_id = d.did;
  31. # 显示查询 92
  32. # 用 join连表 用 on 添加条件
  33. select * from emp e join dept d on e.dep_id = d.did;
  34. # 单独获取数据
  35. # 获取人员的部门名称
  36. select e.*,d.dname from emp e join dept d on e.dep_id = d.did;
  37. -- 获取人员名称和对应部门名称
  38. select e.NAME ,dname from dept inner join emp e on dept.did = e.dep_id;
  39. -- 获取 20150101之后入职的人员名称和对应部门名称
  40. select e.NAME ,dname from dept inner join emp e on dept.did = e.dep_id where e.join_date > '2012-12-01';
  41. -- 获取 薪资大于5000的员工人员名称和对应部门名称
  42. select
  43. e.NAME ,dname
  44. from
  45. dept inner join emp e
  46. on
  47. dept.did = e.dep_id
  48. where
  49. e.salary > 5000;
  50. # 外连接
  51. # 左右外链接
  52. # 查询emp表所有数据和对应的部门信息(左外连接)
  53. select e.*,d.dname from emp e left join dept d on d.did = e.dep_id;
  54. # 查询dept表所有数据和对应的员工信息(右外连接)
  55. select d.*,e.* from emp e right join dept d on d.did = e.dep_id;
  56. # 子查询
  57. # 需求: 查询工资大于孙悟空的人员.
  58. #
  59. # - 孙悟空的工资
  60. select salary from emp where NAME = '孙悟空';
  61. # - 大于 孙悟空工资的人
  62. select * from emp
  63. where salary > (
  64. select salary from emp where NAME = '孙悟空'
  65. );
  66. #子查询练习
  67. # 查询 '财务部' 和 '市场部' 所有的员工信息
  68. # 市场和财务的id
  69. select did from dept where dname = '财务部' or dname = '市场部';
  70. # 查询员工 = 上面条件
  71. select * from emp where emp.id in(
  72. select did from dept where dname = '财务部' or dname = '市场部'
  73. );
  74. # 查询入职日期是 '2011-11-11' 之后的员工信息和部门信息
  75. # 用外连接 子查询虚拟表
  76. select *from emp e where e.join_date > '2011-11-11';
  77. #
  78. select *
  79. from (select *from emp e where e.join_date > '2011-11-11') e join dept d on d.did = e.dep_id;
  80. # 插入数据
  81. DROP TABLE IF EXISTS emp;
  82. DROP TABLE IF EXISTS dept;
  83. DROP TABLE IF EXISTS job;
  84. DROP TABLE IF EXISTS salarygrade;
  85. -- 部门表
  86. CREATE TABLE dept (
  87. did INT PRIMARY KEY PRIMARY KEY, -- 部门id
  88. dname VARCHAR(50), -- 部门名称
  89. loc VARCHAR(50) -- 部门所在地
  90. );
  91. -- 职务表,职务名称,职务描述
  92. CREATE TABLE job (
  93. id INT PRIMARY KEY,
  94. jname VARCHAR(20),
  95. description VARCHAR(50)
  96. );
  97. -- 员工表
  98. CREATE TABLE emp (
  99. id INT PRIMARY KEY, -- 员工id
  100. ename VARCHAR(50), -- 员工姓名
  101. job_id INT, -- 职务id
  102. mgr INT , -- 上级领导
  103. joindate DATE, -- 入职日期
  104. salary DECIMAL(7,2), -- 工资
  105. bonus DECIMAL(7,2), -- 奖金
  106. dept_id INT, -- 所在部门编号
  107. CONSTRAINT emp_jobid_ref_job_id_fk FOREIGN KEY (job_id) REFERENCES job (id),
  108. CONSTRAINT emp_deptid_ref_dept_id_fk FOREIGN KEY (dept_id) REFERENCES dept (did)
  109. );
  110. -- 工资等级表
  111. CREATE TABLE salarygrade (
  112. grade INT PRIMARY KEY, -- 级别
  113. losalary INT, -- 最低工资
  114. hisalary INT -- 最高工资
  115. );
  116. -- 添加4个部门
  117. INSERT INTO dept(did,dname,loc) VALUES
  118. (10,'教研部','北京'),
  119. (20,'学工部','上海'),
  120. (30,'销售部','广州'),
  121. (40,'财务部','深圳');
  122. -- 添加4个职务
  123. INSERT INTO job (id, jname, description) VALUES
  124. (1, '董事长', '管理整个公司,接单'),
  125. (2, '经理', '管理部门员工'),
  126. (3, '销售员', '向客人推销产品'),
  127. (4, '文员', '使用办公软件');
  128. -- 添加员工
  129. INSERT INTO emp(id,ename,job_id,mgr,joindate,salary,bonus,dept_id) VALUES
  130. (1001,'孙悟空',4,1004,'2000-12-17','8000.00',NULL,20),
  131. (1002,'卢俊义',3,1006,'2001-02-20','16000.00','3000.00',30),
  132. (1003,'林冲',3,1006,'2001-02-22','12500.00','5000.00',30),
  133. (1004,'唐僧',2,1009,'2001-04-02','29750.00',NULL,20),
  134. (1005,'李逵',4,1006,'2001-09-28','12500.00','14000.00',30),
  135. (1006,'宋江',2,1009,'2001-05-01','28500.00',NULL,30),
  136. (1007,'刘备',2,1009,'2001-09-01','24500.00',NULL,10),
  137. (1008,'猪八戒',4,1004,'2007-04-19','30000.00',NULL,20),
  138. (1009,'罗贯中',1,NULL,'2001-11-17','50000.00',NULL,10),
  139. (1010,'吴用',3,1006,'2001-09-08','15000.00','0.00',30),
  140. (1011,'沙僧',4,1004,'2007-05-23','11000.00',NULL,20),
  141. (1012,'李逵',4,1006,'2001-12-03','9500.00',NULL,30),
  142. (1013,'小白龙',4,1004,'2001-12-03','30000.00',NULL,20),
  143. (1014,'关羽',4,1007,'2002-01-23','13000.00',NULL,10);
  144. -- 添加5个工资等级
  145. INSERT INTO salarygrade(grade,losalary,hisalary) VALUES
  146. (1,7000,12000),
  147. (2,12010,14000),
  148. (3,14010,20000),
  149. (4,20010,30000),
  150. (5,30010,99990);
  151. -- 练习
  152. # 查询员工编号,员工姓名,工资,职务名称,职务描述
  153. select
  154. e.id,e.ename , e.salary , j.jname ,j.description
  155. from emp e inner join job j on e.job_id = j.id;
  156. # 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
  157. select
  158. e.id,e.ename , e.salary , j.jname ,j.description , d.dname,d.loc
  159. from
  160. emp e inner join
  161. job j join dept d
  162. on e.dept_id = d.did and e.job_id = j.id;
  163. # 查询员工姓名,工资,工资等级
  164. select e.ename ,e.salary , s.grade
  165. from emp e join salarygrade s on e.salary between s.losalary and s.hisalary;
  166. # 查询最高工资和最低工资的员工信息
  167. select MAX(salary) from emp;
  168. select MIN(salary) from emp;
  169. select * from emp where salary in ((select MAX(salary) from emp),(select MIN(salary) from emp));
  170. select * from emp where salary in (
  171. (select salary from emp order by salary desc limit 1),
  172. (select MIN(salary) from emp));
  173. # 查询出部门编号、部门名称、部门位置、部门人数
  174. 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;
  175. 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
  176. # 查看事务
  177. select @@autocommit;
  178. # set 设置 0 手动提交事务
  179. set @@autocommit = 0;
  180. # 修改数据
  181. # 修改person内容
  182. update person set name = 'ls' where id = 1;
  183. commit ;
  184. # 后面 jdbc mybatis 事务 spring 事务