IN 操作符允许您在 WHERE 子句中规定多个值。
在本教程中,我们将使用 RUNOOB 样本数据库。
下面是选自 "Websites" 表的数据:
+----+--------------+---------------------------+-------+---------+ | id | name | url | alexa | country | +----+--------------+---------------------------+-------+---------+ | 1 | Google | https://www.google.cm/ | 1 | USA | | 2 | 淘宝 | https://www.taobao.com/ | 13 | CN | | 3 | 菜鸟教程 | http://www.runoob.com/ | 4689 | CN | | 4 | 微博 | http://weibo.com/ | 20 | CN | | 5 | Facebook | https://www.facebook.com/ | 3 | USA | | 7 | stackoverflow | http://stackoverflow.com/ | 0 | IND | +----+---------------+---------------------------+-------+---------+
下面的 SQL 语句选取 name 为 "Google" 或 "菜鸟教程" 的所有网站:
执行输出结果:
IN 与 = 的异同
IN
SELECT column_name(s) FROM table_name WHERE column_name IN (value1,value2,...);
=
SELECT column_name(s) FROM table_name WHERE column_name=value1;
in 与 = 的转换
select * from Websites where name in ('Google','菜鸟教程');
可以转换成 = 的表达:
select * from Websites where name='Google' or name='菜鸟教程';