select sub.name from subject sub
left join class c on c.subject_id = sub.id
where
c.external_name like "%${B2}%"
group by sub.name
参考填报下拉框联动-https://help.fanruan.com/finereport/doc-view-608.html
用到like的话,直接改成
where ${if(len(B2)=0,"1=2","c.external_name like '%"+B2+"%'")}
联动上了的话本来二级就会为空啊,你一级没填二级还有数据显示是有问题的,模板放上来一下
数据字典sql的条件写成where name = '${name}' 这种格式,不要用where 1=1
你肯定联动控件的数据字典里面写了${if(),"","and xxx=xxx"}
把这个去掉,直接写and xxx=xxx