SQL 两个结果集拼接起来的有关问题

SQL 两个结果集拼接起来的问题

SQL code

select Sid,count(*)as Num from t_forums a group by Sidselect b.*,c.SectionName from t_forums b,t_sections cwhere b.Id=(select max(id)as Id from t_forums where Sid=c.Id)

SQL code

select a.*,       b.*,       c.SectionName from t_forums b,t_sections c,(select Sid,       count(*)as Num from t_forums a group by Sid)awhere b.Id=(select max(id)as Id from t_forums where Sid=c.Id)and a.sid=b.sid