精心整理的SQL语句集锦,助力求职之路,祝您面试顺利!
SQL语句集锦
(以下仅为示例,请根据实际情况进行调整)
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基础查询
- 查询所有员工信息:
SELECT * FROM employees;
- 查询姓名和部门的员工信息:
SELECT name, department FROM employees;
- 查询特定部门的员工:
SELECT * FROM employees WHERE department = 'Sales';
- 查询所有员工信息:
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数据筛选
- 查询薪资大于50000的员工:
SELECT * FROM employees WHERE salary > 50000;
- 查询姓名以'J'开头的员工:
SELECT * FROM employees WHERE name LIKE 'J%';
- 查询在2022年入职的员工:
SELECT * FROM employees WHERE YEAR(hire_date) = 2022;
- 查询薪资大于50000的员工:
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数据排序
- 按薪资降序排列员工信息:
SELECT * FROM employees ORDER BY salary DESC;
- 按部门升序,再按薪资降序排列员工信息:
SELECT * FROM employees ORDER BY department ASC, salary DESC;
- 按薪资降序排列员工信息:
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聚合函数
- 计算员工总数:
SELECT COUNT(*) FROM employees;
- 计算平均薪资:
SELECT AVG(salary) FROM employees;
- 查询每个部门的最高薪资:
SELECT department, MAX(salary) FROM employees GROUP BY department;
- 计算员工总数:
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连接查询
- 查询员工及其所在部门信息:
SELECT e.name, d.department_name FROM employees e JOIN departments d ON e.department_id = d.department_id;
- 查询员工及其所在部门信息:
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子查询
- 查询薪资高于平均薪资的员工:
SELECT * FROM employees WHERE salary > (SELECT AVG(salary) FROM employees);
- 查询薪资高于平均薪资的员工:
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数据修改
- 将员工'John Doe'的薪资改为60000:
UPDATE employees SET salary = 60000 WHERE name = 'John Doe';
- 删除销售部门的所有员工:
DELETE FROM employees WHERE department = 'Sales';
- 将员工'John Doe'的薪资改为60000:
更多SQL语句示例,请参考相关资料或在线教程。
祝您求职顺利,找到理想工作!