Orcle基本语句（四）

 --显示员工的编号,姓名,工资,工资级别,所在部门的名称;(使用emp表)
 SELECT * FROM emp;
 SELECT * FROM salgrade;
 SELECT * FROM dept;
 SELECT e.empno, e.ename, e.sal, s.grade, d.dname
   FROM emp e, salgrade s, dept d
  WHERE e.sal BETWEEN s.losal AND s.hisal
    AND e.deptno = d.deptno;
 --现要求查询出每个雇员的姓名，工资，部门名称，工资在公司的等级（salgrade），及领导姓名及工资所在公司的等级
 SELECT e1.empno,
        e1.ename,
        e1.sal,
        s1.grade 员工工资等级,
        d.dname,
        e2.ename,
        e2.sal   领导工资,
        s2.grade 领导工资等级
   FROM emp e1, salgrade s1, salgrade s2, dept d, emp e2
  WHERE e1.sal BETWEEN s1.losal AND s1.hisal
    AND e1.deptno = d.deptno
    AND e1.mgr = e2.empno
    AND e2.sal BETWEEN s2.losal AND s2.hisal
  ORDER BY e1.sal;
 --外联接
 SELECT d.*, e.* FROM dept d, emp e WHERE d.deptno(+) = e.deptno; -- 右外联接(一)
 SELECT d.*, e.* FROM dept d, emp e WHERE d.deptno = e.deptno(+); --左外联接（一）
 SELECT d.*, e.* FROM dept d RIGHT JOIN emp e ON d.deptno = e.deptno; -- 右外联接（二）
 SELECT d.*, e.* FROM dept d LEFT JOIN emp e ON d.deptno = e.deptno; -- 左外联接（二）

 --查询员工编号，姓名，部门编号,部门名称（左外连接）
 SELECT e.empno, e.ename, e.deptno, d.dname
   FROM emp e
   LEFT JOIN dept d
     ON e.deptno = d.deptno;
 SELECT e.empno, e.ename, e.deptno, d.dname
   FROM emp e, dept d
  WHERE e.deptno = d.deptno(+);
 --查询员工编号，姓名，部门编号,部门名称（右外连接）
 SELECT e.empno, e.ename, e.deptno, d.dname
   FROM emp e
  RIGHT JOIN dept d
     ON e.deptno = d.deptno;
 SELECT e.empno, e.ename, e.deptno, d.dname
   FROM emp e, dept d
  WHERE e.deptno(+) = d.deptno;
 --查询30号部门的员工
 SELECT * FROM emp;
 SELECT * FROM emp e JOIN dept d USING (deptno) WHERE deptno = 30;

 --查询员工编号，姓名，部门编号,部门名称，职务编号，职务名称并且薪资大于8000 按照薪资降序排列
 SELECT e.employee_id,
        e.last_name,
        d.department_id,
        d.department_name,
        e.salary,
        j.job_id,
        j.job_title
   FROM employees e
  INNER JOIN departments d
     ON e.department_id = d.department_id
  INNER JOIN jobs j
     ON e.job_id = j.job_id
  WHERE e.salary > 8000
  ORDER BY e.salary DESC;
 COMMIT;
 --查询所有部门的编号，部门名称，部门经理ID，部门经理姓名，部门所在的城市，国家，地区
 SELECT * FROM departments;
 SELECT * FROM locations;
 SELECT * FROM employees;
 SELECT * FROM countries;
 SELECT d.department_id   部门编号,
        d.department_name 部门名称,
        d.manager_id      部门经理id,
        e.last_name       部门经理姓名,
        l.city            部门所在城市,
        c.country_name     部门所在国家,
        l.state_province  部门所在地区
   FROM departments d
   LEFT JOIN employees e
     ON d.manager_id = e.manager_id
   LEFT JOIN locations l
     ON d.location_id = l.location_id
     LEFT JOIN countries c
     ON l.country_id = c.country_id
  ORDER BY d.department_id;
 --查询谁的工资比'ABEL’
 select * from employees;
 SELECT first_name || last_name NAME, salary
   FROM employees
  WHERE salary >= (SELECT salary FROM employees WHERE last_name = 'Abel')
  ORDER BY salary;
 ----查询工资比7654高，同时与7788从事相同工作的全部雇员信息(emp)
 SELECT * FROM emp;
 SELECT *
   FROM emp
  WHERE sal > (SELECT sal FROM emp WHERE empno = 7654)
    AND job = (SELECT job FROM emp WHERE empno = 7788);
 --部门名称，部门员工数，部门平均工资，部门的最低收入雇员的姓名
 SELECT d.dname, e.deptno, tmp.c, tmp.a, tmp.m, e.ename
   FROM dept d,
        emp e,
        (SELECT e.deptno, COUNT(e.deptno) c, AVG(sal) a, MIN(sal) m
        FROM emp e GROUP BY e.deptno) tmp
  WHERE d.deptno = e.deptno
  AND e.sal = tmp.m;
 --求出每个部门的最低工资的雇员信息
 SELECT *
   FROM emp e, (SELECT MIN(sal) m FROM emp GROUP BY deptno) tmp
  WHERE e.sal = tmp.m;
  SELECT *
   FROM emp e
  WHERE e.sal in (SELECT MIN(sal) m FROM emp GROUP BY deptno);
 ----查询工资与10部门中的任意一个人相等的员工信息
 select * from emp;
 SELECT * FROM emp WHERE sal in (SELECT sal FROM emp WHERE deptno =  10);
 SELECT * FROM emp WHERE sal = ANY(SELECT sal FROM emp WHERE deptno =  10);
 --查询所有是部门经理的员工(employees)
 SELECT * FROM employees;
 SELECT *
   FROM employees
  WHERE employee_id IN (SELECT manager_id FROM employees) ORDER BY employee_id;
  SELECT *
   FROM employees e1
  WHERE  EXISTS(SELECT manager_id FROM employees e2 WHERE e1.employee_id = e2.manager_id) ORDER BY employee_id;
 ----查询所有不是部门经理的员工(employees)
 SELECT *
   FROM employees
  WHERE employee_id  <> ALL(SELECT manager_id FROM employees WHERE manager_id IS NOT NULL ) ORDER BY employee_id;
  SELECT *
   FROM employees
  WHERE  employee_id NOT IN (SELECT manager_id FROM employees WHERE manager_id IS NOT NULL) ORDER BY employee_id;
  SELECT *
   FROM employees e1
  WHERE NOT EXISTS(SELECT manager_id FROM employees e2 WHERE e1.employee_id = e2.manager_id) ORDER BY employee_id;
  --查询所有员工人数不少于3人的部门信息(employees)
  SELECT * FROM departments;
  SELECT * FROM employees;
  SELECT d.*,tmp.c
    FROM departments d INNER JOIN
         (SELECT department_id,COUNT(employee_id) c FROM employees GROUP BY department_id) tmp
   ON tmp.c >= 3 AND d.department_id = tmp.department_id;
  ----查询姓名，职位，薪资在按照 职位，薪资 去重复之后存在的数据
  SELECT ename,job,sal FROM emp WHERE exists(select distinct job,sal from emp);
 --查询是本部门入职最早的但不是部门经理的员工
 SELECT * FROM employees;
 --1.查询本部门入职最早的员工
 SELECT MIN(hire_date) FROM employees GROUP BY department_id;
 --2.查询不是部门经理的员工
 SELECT *
   FROM employees e1
  WHERE NOT EXISTS(SELECT manager_id FROM employees e2 WHERE e1.employee_id = e2.manager_id) ORDER BY employee_id;
 --3.结合1、2给出本部门入职最早的但不是部门经理的员工
 SELECT *
   FROM employees e1
  WHERE NOT EXISTS
  (SELECT manager_id
           FROM employees e2
          WHERE e1.employee_id = e2.manager_id)
    AND hire_date IN
        (SELECT MIN(hire_date) FROM employees GROUP BY department_id)
  ORDER BY employee_id;
 --查询所有工资超过本部门平均工资的员工
 --1. 查询各个部门的平均工资
 SELECT department_id,AVG(salary) avgsa FROM employees GROUP BY department_id;
 --2.
 SELECT e.*, tmp.avgsa
   FROM employees e,
        (SELECT department_id, AVG(salary) avgsa
           FROM employees
          GROUP BY department_id) tmp
  WHERE e.department_id = tmp.department_id
    AND e.salary > tmp.avgsa;

 --查询所有换过职务的员工
 SELECT e.*,jh.* FROM employees e,job_history jh WHERE e.employee_id = jh.employee_id;
 SELECT e.*, jh.*
   FROM employees e
  INNER JOIN job_history jh
     ON e.employee_id = jh.employee_id;