MySQL中USING 和 HAVING 用法实例简析

时间:2022-05-12 02:04:52

本文实例讲述了MySQLUSINGHAVING 用法。分享给大家供大家参考,具体如下:

USING

用于表连接时给定连接条件(可以理解为简写形式),如

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SELECT * FROM table1
JOIN table2 ON table1.id = table2.id

使用 USING 可以写为

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SELECT * FROM table1
JOIN table2 USING(id)

HAVING

引入 HAVING 是因为 WHERE 无法和统计函数一起使用

如表 order (定单)有如下字段:

id, date, price, customer

查找订单总额少于2000的客户可以这样写:

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SELECT customer, SUM(price) FROM order
GROUP BY customer
HAVING SUM(price)<2000

查找指定客户中订单超过1500的订单总额:

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SELECT customer,SUM(price) FROM order
WHERE customer='…' OR customer = '…'
GROUP BY customer
HAVING SUM(price) > 1500

希望本文所述对大家MySQL数据库计有所帮助。

原文链接:https://blog.csdn.net/qq_42176520/article/details/89852547