兩個表按照回復量排序怎麼寫sql?
t1（標題表）
id
t2（回復表1,會有多條回復，關係：t2.t1id=t1.id）
t1id
＝＝＝＝＝＝＝＝＝＝＝＝
列出t1的數據，以回復數多少排序，怎麼寫？
[解决办法]
select a.*,b.cnt as 回复数
from t1 as a
inner join (select t1id,count(*) as cnt from t2 group by t1id) as b on a.id=b.t1id
order by b.cnt desc
[解决办法]
--?这样?
select t1.id from t1 join t2 on t1.id=t2.t1id group by t1.id order by count(*) desc
[解决办法]
select t1.id ，count(1) from t1 left join t2 on t1.id=t2.t1id group by t1.id order by count(1) desc
[解决办法]
select t1.id , count(*) 回复数 from t2,t1 where t2.t1id = t1.id group by t1.id order by 回复数 desc
