mysql -3练习（分组查询后再次筛选，顺逆序排序）

Posted 2020-11-02 张锐0328

插入如下的表格

/*插入表格*/
CREATE TABLE sanguo(
  empno   INT,
  ename   VARCHAR(20),
  job     VARCHAR(20),
  mgr      INT,
  hiredte   DATE,
  sal       DOUBLE,
  comm       DOUBLE,
  deptno     INT
  );
  SELECT * FROM sanguo;
  
  ALTER TABLE sanguo CHANGE COLUMN hiredte hiredate DATE;
  /*填入数据*/
  INSERT INTO sanguo VALUES(1001,\'甘宁\',\'文员\',1013,\'20001217\',8000.00,NULL,20);
  INSERT INTO sanguo VALUES(1002,\'戴绮斯\',\'销售员\',1006,\'2001-02-20\',16000.00,3000.00,30);
  INSERT INTO sanguo VALUES(1003,\'殷天正\',\'销售员\',1006,\'2001-02-22\',12500.00,5000.00,30);
  INSERT INTO sanguo VALUES(1004,\'刘备\',\'经理\',1009,\'2001-04-02\',29750.00,NULL,20);
  INSERT INTO sanguo VALUES(1005,\'谢逊\',\'销售员\',1006,\'2001-09-28\',12500.00,14000.00,30);
  INSERT INTO sanguo VALUES(1006,\'关羽\',\'经理\',1009,\'2001-05-01\',28500.00,NULL,30);
  INSERT INTO sanguo VALUES(1007,\'张飞\',\'经理\',1009,\'2001-09-01\',24500.00,NULL,10);
  INSERT INTO sanguo VALUES(1008,\'诸葛亮\',\'分析师\',1004,\'2007-04-19\',30000.00,NULL,20);
  INSERT INTO sanguo VALUES(1009,\'曾阿牛\',\'董事长\',NULL,\'2001-11-17\',50000.00,NULL,10);
  INSERT INTO sanguo VALUES(1010,\'韦一笑\',\'销售员\',1006,\'2001-09-08\',15000.00,0.00,30);
  INSERT INTO sanguo VALUES(1011,\'周泰\',\'文员\',1008,\'2007-05-23\',11000.00,NULL,20);
  INSERT INTO sanguo VALUES(1012,\'程普\',\'文员\',1006,\'2001-12-03\',9500.00,NULL,30);
  INSERT INTO sanguo VALUES(1013,\'庞统\',\'分析师\',1004,\'2001-12-03\',30000.00,NULL,20);
  INSERT INTO sanguo VALUES(1014,\'黄盖\',\'文员\',1007,\'2002-01-23\',13000.00,NULL,10);
  INSERT INTO sanguo VALUES(1015,\'张三\',\'保洁员\',1001,\'2013-05-01\',80000.00,50000.00,50);
  
  /*查询所有部门编号为30的员工*/
  SELECT * FROM sanguo WHERE deptno = 30;
  /*查询所有职位为销售员的员工的编号，姓名，部门编号*/
  SELECT empno,ename,deptno FROM sanguo WHERE job = \'销售员\';
  /*查询所有奖金大于工资的员工*/
  SELECT * FROM sanguo WHERE comm > sal ;
  /*查询所有奖金大于工资60%的员工*/
  SELECT * FROM sanguo WHERE comm > (0.6*sal);
  /*查询所有部门编号为10同时是经理或者部门编号为20同时是销售员的员工*/
  SELECT * FROM sanguo WHERE ( deptno = 10 AND job = \'经理\') OR (deptno = 20 AND job = \'销售员\' );
  /*查询所有部门编号为10同时是经理或者部门编号为20同时是销售员或奖金大于20000的员工*/
  SELECT * FROM sanguo WHERE ( deptno = 10 AND job = \'经理\') OR (deptno = 20 AND job = \'销售员\' )OR(comm >= 20000);
   /*查询所有没有奖金或奖金小于1000的员工*/
  SELECT ename FROM sanguo WHERE comm IS NULL OR comm < 1000;
   /*查询所有名字是三个字的员工*/
  SELECT ename FROM sanguo WHERE ename LIKE \'___\';
   /*查询所有2000年加入公司的员工*/
  SELECT * FROM sanguo WHERE hiredate LIKE \'2000%\';
    /*查询所有员工详细信息，用编号升序排序*/
  SELECT * FROM sanguo ORDER BY empno ASC;
   /*查询所有员工详细信息，用工资降序排序，如果工资相同使用入职日期升序排序*/
  SELECT * FROM sanguo ORDER BY sal DESC,hiredate ASC;
   /*查询姓周的两个名字的员工。*/
  SELECT * FROM sanguo WHERE ename LIKE \'周_\';
  /*查询所有姓张的员工。*/
  SELECT * FROM sanguo WHERE ename LIKE \'张%\';
  /*查询该部门有多少个岗位，每个岗位有多少人。*/
  SELECT job,COUNT(*) FROM sanguo GROUP BY job;
  /*查询哪个岗位中人数大于3。*/
  SELECT job FROM sanguo GROUP BY job HAVING COUNT(*)>3;