sql之表的表达式
1、派生表 实质：就是特殊的子查询（将查询结果放在from后面） 含有一张Order表： 看下面的sql语句： orderid,orderdate,custid ( orderid,orderdate,custid,ROW_NUMBER() ) as t -- 表名必须起别名
1、派生表
实质：就是特殊的子查询（将查询结果放在from后面）
含有一张Order表：
看下面的sql语句：
orderid,orderdate,custid ( orderid,orderdate,custid,ROW_NUMBER() ) as t--表名必须起别名 ，
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