mysql 行子查询

#案例：查询员工编号最小且工资最高的员工信息

SELECT *
FROM employees
WHERE (employee_id,salary)=(

	SELECT MIN(employee_id),MAX(salary)
	FROM employees
);

由以下代码演变而来

SELECT *
FROM employees
WHERE employee_id=(
	SELECT MIN(employee_id)
	FROM employees
) AND salary=(
	SELECT MAX(salary)
	FROM employees
);