select a.id,case a.emergency_level when 1 then '普通' when 2 then '紧急' when 3 then '特急' end emergencylevel,
a.task_name taskname,a.task_content taskcontent,to_char(a.creater_time,'yyyy-mm-dd') creatertime,
case a.status when 0 then '草拟' when 1 then '待签收' when 2 then '处理中' when 3 then '待审核' else '办结' end status
,b.name handlename,c.name handleorg
from task_main_content a
left join security_account b on a.handler_account_id=b.id
left join security_organization c on a.handler_org_id=c.id
我这条SQL语句，为什么最后两个字段查不到，怎么改，求大神指导
