MYSQL的select语句查询；运算符课后练习

#第三章基本的select语句查询课后练习

#1.查询员工12个月的工资总和，并起名为ANNUAL SALARY
#一个理解是只算工资的话
SELECT employee_id,first_name,last_name,salary*12 AS “ANNUAL SALARY”
FROM employees;

#另一个理解是工资加奖金
SELECT employee_id,first_name,last_name,salary12(1+IFNULL(commission_pct,0)) AS"年工资"
FROM employees;

#2.查询employees表中去除重复的job_id以后的数据
SELECT DISTINCT job_id
FROM employees;

#3.查询工资大于12000的员工的姓名和工资
SELECT first_name,last_name,salary
FROM employees
WHERE salary>12000;

#4.查询员工号为176的员工的姓名和部门号
SELECT first_name,last_name,department_id
FROM employees
WHERE employee_id=176;

#5.显示表departments的结构，并查询其中的全部数据
DESC departments;

#第四章运算符课后练习
#1.选择工资不在5000到12000的员工姓名和工资
SELECT last_name,salary
FROM employees
WHERE salary NOT BETWEEN 5000 AND 12000;

#2.选择在20或50号部门工作的员工姓名和部门号
SELECT last_name,department_id
FROM employees
#where department_id=20 or department_id=50;
WHERE department_id IN(20,50);

#3.选择公司中没有管理者的员工姓名以及job_id
SELECT last_name,job_id
FROM employees
WHERE manager_id IS NULL;
#或 where manager_id <=>null;

#4.选择公司中没有奖金的员工姓名，工资和奖金级别
SELECT last_name,salary,commission_pct
FROM employees
WHERE commission_pct IS NOT NULL;
#或 where not manage_id<=>null;

#5.选择员工的姓名的第三个字母是a的员工姓名
SELECT last_name
FROM employees
WHERE last_name LIKE’__a%';

#6.选择姓名中有a和k的员工姓名
SELECT last_name
FROM employees
WHERE last_name LIKE’%a%k%‘OR’%k%a%';

#7.显示出表employees表中first_name以’e’结尾的员工信息
SELECT first_name,last_name
FROM employees
WHERE first_name LIKE’%e’;

**#下边使用正则表达式 字母$表示以什么字母结尾\ast \ast SELECTfirs{t}_{n}ame,las{t}_{n}ameFROMemployeesWHEREfirs{t}_{n}ameREGEX{P}^{\prime }e$’;

SELECT first_name,last_name
FROM employees
WHERE first_name RLIKE ‘e$’;

#8.显示出表employees部门编号在80到100之间的姓名，工种
SELECT last_name,job_id
FROM employees
WHERE department_id BETWEEN 80 AND 100;

#9.显示出表employees表中manage_id是100,101，110的员工信息，工资，管理者id
SELECT last_name,salary,manager_id
FROM employees
WHERE manager_id IN(100,101,110);