select t.orgname,t.type_name,ifnull(sum(t.stoptime),0) as stoptimefrom(SELECT o.keycode as orgcode, o.name as orgname, case when wh.typeid=1 then '故障工单' else '保养工单' end as type_name, wh.stoptimeFROM workorderhistory whleft join organization o on wh.orgid=o.idwhere wh.typeid in (1,3) and wh.orgid =25 and (DATE_FORMAT(wh.technicaldate,'%Y-%m-%d') between '2021-07-01' and '2021-07-19') )t group by t.orgname,t.type_name这个SQL里面type_name的字段,在Navicat中显示的是正常的值,但是在设计器中预览就变成了"????"的值,数据库是MySQL5.7,应该是SQL的问题还是设计器的问题?