1，新聞表news
id 新聞編號
content 新聞內容
title 新聞標題
2，評論表。comment
id 評論編號
content 評論內容
newsId 新聞編號
要求：
使用MySQL查詢評論數量最多的10條新聞
uj5u.com熱心網友回復：
select top 10 a.id,a.content ,a.title ,b.com_qty from news a,(select count(1) as com_qty ,comment.newsId from comment group by comment.newsId ) b where a.newsId = b.newsId order by b.com_qty descuj5u.com熱心網友回復：
不行啊，報錯，，，內個b.com_qty是什么意思啊uj5u.com熱心網友回復：
select *from
(select a.id,count(b.id) as comment_cnt
from
news as a
inner join
comment as b on a.id = b.newsId
) as a
order by comment_cnt desc
limit 10
這樣試試
uj5u.com熱心網友回復：
select *
from
(select a.id,count(b.id) as comment_cnt
from
news as a
inner join
comment as b on a.id = b.newsId
group by a.id
) as a
order by comment_cnt desc
limit 10
少打了group by
uj5u.com熱心網友回復：
select a.id, count(b.id) as content_numfrom new as a
inner join content as b on (a.id = b.newsld)
group by a.id
order by count(b.id) desc
limit 10
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