sql 循环游标的替代方案是什么

SQL循环游标的替代方案

sql
SELECT AVG(salary) FROM employees;

sql
SELECT * FROM employees WHERE salary > (SELECT AVG(salary) FROM employees);

sql
SELECT department, AVG(salary) OVER (PARTITION BY department) AS avg_salary,
       RANK() OVER (ORDER BY AVG(salary) DESC) AS rank
FROM employees;

sql
-- 计算每个部门的平均薪资
SELECT department, AVG(salary) AS avg_salary
FROM employees
GROUP BY department;
-- 找出薪资最高的部门
SELECT department
FROM (
  SELECT department, ROW_NUMBER() OVER (ORDER BY AVG(salary) DESC) AS rank
  FROM employees
  GROUP BY department
) AS ranks
WHERE rank = 1;