26、列出所有员工的姓名、部门名称和工资。

mysql> SELECT

-> e.ename,

-> d.dname,

-> e.sal

-> FROM

-> emp e

-> JOIN

-> dept d

-> ON

-> e.deptno = d.deptno;

+--------+------------+---------+

| ename | dname | sal |

+--------+------------+---------+

| CLARK | ACCOUNTING | 2450.00 |

| KING | ACCOUNTING | 5000.00 |

| MILLER | ACCOUNTING | 1300.00 |

| SMITH | RESEARCH | 800.00 |

| JONES | RESEARCH | 2975.00 |

| SCOTT | RESEARCH | 3000.00 |

| ADAMS | RESEARCH | 1100.00 |

| FORD | RESEARCH | 3000.00 |

| ALLEN | SALES | 1600.00 |

| WARD | SALES | 1250.00 |

| MARTIN | SALES | 1250.00 |

| BLAKE | SALES | 2850.00 |

| TURNER | SALES | 1500.00 |

| JAMES | SALES | 950.00 |

+--------+------------+---------+

27、列出所有部门的详细信息和人数

mysql> SELECT

-> d.*, count(e.ename) AS empcount

-> FROM

-> dept d

-> LEFT JOIN

-> emp e

-> ON

-> d.deptno = e.deptno

-> GROUP BY

-> d.deptno, d.dname, d.loc;

+--------+------------+----------+----------+

| DEPTNO | DNAME | LOC | empcount |

+--------+------------+----------+----------+

| 10 | ACCOUNTING | NEW YORK | 3 |

| 20 | RESEARCH | DALLAS | 5 |

| 30 | SALES | CHICAGO | 6 |

| 40 | OPERATIONS | BOSTON | 0 |

+--------+------------+----------+----------+

28、列出各种工作的最低工资及从事此工作的雇员姓名

mysql> SELECT

-> e.ename,

-> e.sal

-> FROM

-> emp e

-> JOIN (

-> SELECT

-> min(sal) AS minsal,

-> job

-> FROM

-> emp

-> GROUP BY

-> job

-> ) t

-> ON

-> t.minsal = e.sal

-> AND

-> t.job = e.job;

+--------+---------+

| ename | sal |

+--------+---------+

| SCOTT | 3000.00 |

| FORD | 3000.00 |

| SMITH | 800.00 |

| CLARK | 2450.00 |

| KING | 5000.00 |

| WARD | 1250.00 |

| MARTIN | 1250.00 |

+--------+---------+

29、列出各个部门的MANAGER(领导)的最低薪金

mysql> SELECT

-> deptno,

-> min(sal)

-> FROM

-> emp

-> WHERE

-> job = 'manager'

-> GROUP BY

-> deptno;

+--------+----------+

| deptno | min(sal) |

+--------+----------+

| 10 | 2450.00 |

| 20 | 2975.00 |

| 30 | 2850.00 |

+--------+----------+

30、列出所有员工的年工资,按年薪从低到高排序

mysql> SELECT

-> ename,

-> (sal + ifnull(comm, 0))*12 AS yearsal

-> FROM

-> emp

-> ORDER BY

-> yearsal ASC;

+--------+----------+

| ename | yearsal |

+--------+----------+

| SMITH | 9600.00 |

| JAMES | 11400.00 |

| ADAMS | 13200.00 |

| MILLER | 15600.00 |

| TURNER | 18000.00 |

| WARD | 21000.00 |

| ALLEN | 22800.00 |

| CLARK | 29400.00 |

| MARTIN | 31800.00 |

| BLAKE | 34200.00 |

| JONES | 35700.00 |

| FORD | 36000.00 |

| SCOTT | 36000.00 |

| KING | 60000.00 |

+--------+----------+

31、求出员工领导的薪水超过3000的员工名称与领导名称

mysql> SELECT

-> a.ename AS empname,

-> b.ename AS leadername

-> FROM

-> emp a

-> JOIN

-> emp b

-> ON

-> a.mgr = b.empno

-> WHERE

-> b.sal > 3000;

+---------+------------+

| empname | leadername |

+---------+------------+

| JONES | KING |

| BLAKE | KING |

| CLARK | KING |

+---------+------------+

32、求出部门名称中,带'S'字符的部门员工的工资合计、部门人数.

mysql> SELECT

-> sum(sal),

-> count(ename)

-> FROM

-> emp

-> WHERE

-> ename LIKE '%S%'

-> GROUP BY

-> deptno;

+----------+--------------+

| sum(sal) | count(ename) |

+----------+--------------+

| 7875.00 | 4 |

| 950.00 | 1 |

+----------+--------------+

33、给任职日期超过30年的员工加薪10%.

create table emp_bak as select * from emp;

update emp_bak set sal = sal*1.1 where (to_days(now()) - to_days(hiredate))/365 > 30;