Question

select * from (select top 10 * from ( select sum(number) as amount,ISBN from tb_Order_detail group

select * from (select top 10 * from ( select sum(number) as amount,ISBN from tb_Order_detail group by ISBN )as tab order by amount desc) o inner join tb_bookinfo b on o.ISBN=b.ISBN order by o.amount desc
帮忙分析解释一下这个语句 特别是后边的这个是什么意思啊 o inner join tb_bookinfo b on o.ISBN=b.ISBN order by o.amount desc

Answer 1

INNER JOIN 运算
组合两个表中的记录，只要在公共字段之中有相符的值。

o 是(select top 10 * from ( select sum(number) as amount,ISBN from tb_Order_detail group by ISBN )as tab order by amount desc) 作为o表，就是组合o表和 tb_bookinfo 表（b表）两个表的记录，只取出这两个表里面相符的值，条件就是o.ISBN=b.ISBN order by o.amount desc

Answer 2

外链///O表连接B表..好像吧