摘要:
SELECT currency_id, COUNT(*) AS "Count" FROM tablea WHERE currency_id = 0 GROUP BY currency_id HAVING COUNT(*) >= 3; [注意] 语法位置 where条件语句中的条件必须在select中 阅读全文
摘要:
-- remove only the employees DELETE e FROM Employees e JOIN Department d ON e.department_id = d.department_id WHERE d.name = 'Sales'; -- remove employ 阅读全文