如果你的折扣率字段是数值,那就可以在数据集sql中过滤
select * from 表 where 1=1
${if(len(开始折扣率控件名)=0,""," and 折扣率字段 >"+开始折扣率控件名)}
${if(len(结束折扣率控件名)=0,""," and 折扣率字段 >"+结束折扣率控件名)}