varsql=$"select * from dc_daily_logistics_supplier_transaction where suppliername='{item.suppliername}' and day<'{item.day.ToString("yyyy-MM-dd")}' order by id desc limit 1";
varsql=$"select * from dc_daily_logistics_supplier_transaction where suppliername='{item.suppliername}' and day<'{item.day.ToString("yyyy-MM-dd")}' order by day desc limit 1";