inner join (select exam_id,school_id,school_name from single_yuejuan_source.bus_exam_student group exam_id,school_id,school_name) b on a.exam_id=b.exam_id</sql>
<sql>select case when (select count(*) from task_list where task_status=1 and id=${task_id} and del_flag=0)>0 then 1 else 0 end is_run</sql>
<sql>select case when (select count(*) from task_list where task_status=1 and id=${task_id} and del_flag=0 and source_type=1)>0 then 1 else 0 end is_run</sql>