你可能感興趣的試題

通過創(chuàng)建“雇員”表和“部門”表的視圖來顯示每個部門的薪金信息。 執(zhí)行以下語句時(shí)會發(fā)生什么情況（）
CREATE OR REPLACE VIEW sal_dept
AS SELECT SUM(e.salary) sal, d.department_name
FROM employees e, departments d
WHERE e.department_id = d.department_id
GROUP BY d.department_name
ORDER BY d.department_name.