初步认识下Oracel的ROW_NUMBER()Over(partition by order by )
-----删除重复数据deletefromcwgs.loan_buy_extendoprwhereoprnoin(selectoprnofrom(selectd.oprno,d.y_contno,row_number()over(partitionbyy_contnoorderbyy_contno)row_flagfromcwgs.loan_buy_extendoprd)twheret.row_f