如何把两条SELECT语句的结果合在同一张表中？？

Question

select a.*, b.*
from (
(select id,submittime,msgcontent,title,viewstate,receiver from school_attach.submittest s left join school_attach.viewcheck v on s.done=v.viewid left join school2.users u on u.userid=s.sendor) a,
(select u.username from school2.users u,school_attach.submittest s where s.receiver=u.userid) b
)

Answer 1

应该这样。
select *
from 
(select id,submittime,msgcontent,title,viewstate,receiver from school_attach.submittest s left join school_attach.viewcheck v on s.done=v.viewid left join school2.users u on u.userid=s.sendor) a,
(select u.username from school2.users u,school_attach.submittest s where s.receiver=u.userid) b