SQL HAVING 关键字
HAVING
HAVING 命令用于与聚合函数一起使用,替代 WHERE。
以下 SQL 列出了每个国家的客户数量。只包含拥有超过 5 个客户的国家:
实例
SELECT COUNT(CustomerID), Country FROM Customers GROUP BY Country HAVING COUNT(CustomerID) > 5;
以下 SQL 列出了每个国家的客户数量,并按数量从高到低排序(只包含拥有超过 5 个客户的国家):
实例
SELECT COUNT(CustomerID), Country FROM Customers GROUP BY Country HAVING COUNT(CustomerID) > 5 ORDER BY COUNT(CustomerID) DESC;