sql-删除delete涉及到三个表，这个时候就要使用from，比如这样

delete y from dbo.XZXK_BANJIE b ,YJDC_YELLOWRED_CONTENT y , dbo.XZXK_SHOULI s
where b.shoulioid=s.shoulioid and y.caseid=s.caseid and b.BJSJ > y.SEND_YELLOWRED_DATE