-- 查询存在薪资低于60000的员工的部门信息SELECTDISTINCT department
FROM employees e
WHEREEXISTS(SELECT1FROM employees
WHERE salary <60000AND department = e.department
);
10、使用IN和NOT IN进行条件匹配:
-- 查询年龄为28、29或32岁的员工信息SELECT*FROM employees WHERE age IN(28,29,32);-- 查询不属于HR和IT部门的员工信息SELECT*FROM employees WHERE department NOTIN('HR','IT');
11、使用BETWEEN进行范围匹配:
-- 查询薪资在50000到60000之间的员工信息SELECT*FROM employees WHERE salary BETWEEN50000AND60000;
12、使用LIKE和NOT LIKE进行模糊匹配:
-- 查询姓名以'lfsun'开头的员工信息SELECT*FROM employees WHERE emp_name LIKE'lfsun%';-- 查询姓名不包含'lfsun-1'的员工信息SELECT*FROM employees WHERE emp_name NOTLIKE'%lfsun-1%';
13、使用IS NULL和IS NOT NULL进行空值判断:
-- 查询没有薪资信息的员工信息SELECT*FROM employees WHERE salary ISNULL;-- 查询具有薪资信息的员工信息SELECT*FROM employees WHERE salary ISNOTNULL;