Every derived table must have its own alias(每一个衍生表必须有它自己的别名)
Every derived table must have its own alias(每一个衍生表必须有它自己的别名)
日期:2014-05-16 浏览次数:20442 次
Every derived table must have its own alias(每一个派生表必须有它自己的别名)
每一个派生表必须有它自己的别名 select count(*) from (select t.a from test t group by t.a) 解决办法: select count(*) from (select t.a from test t group by t.a)c