1、问题贴见（这里一个注意点为：coalesce(字段,0) 使用，即判断这个字段是否为NULL，如果为NULL，则为0）
select tt.uname,tt.sumstart,ttt.laststart from
(
select id,name as uname, COALESCE(SUM(start),0) as sumstart from [user] t1 left join team t2
on t1.id=t2.uid group by id,name
) tt,
(
select t1.id,t1.name as uname, COALESCE(start,0)as laststart from [user] t1 left join team t2
on t1.id=t2.uid and data=(select MAX(data) from team)
) ttt
where tt.id=ttt.id;
级联更新表字段
update ST_PPTN_D set LGTD= a.LGTD,LTTD=a.LTTD from ST_STBPRP_B a inner join ST_PPTN_D p on p.STCD=a.STCD;
