Oracle de-weight

Oracle deletes duplicate data with only one query and the SQL statement to delete duplicate records--1, look for redundant records in the table, duplicate records are based on a single field (ID) to determineSelect *  fromTablewhereIdinch(SelectId fromTableGroupByid having Count(Id)> 1) --Example:Select *  fromOrders_tmp2whereCust_nbrinch(SelectCust_nbr fromOrders_tmp2Group  byCust_nbr having Count(CUST_NBR)> 1) --2, delete redundant records in the table, duplicate records are based on a single field (ID) to judge, leaving only the smallest rowID recordsDELETE  fromTableWHERE(ID)inch     ( SELECTId fromTableGROUP  byId having COUNT(ID)> 1)      andROWID not inch(SELECT MIN(ROWID) fromTableGROUP  byId having COUNT(*)> 1); --3. Find redundant duplicate records (multiple fields) in the tableSelect *  fromTable Awhere(A.ID,A.SEQ)inch(SelectId,seq fromTableGroup  byId,seq having Count(*)> 1) --4. Delete extra duplicate records (multiple fields) in the table, leaving only the record with ROWID minimumDelete  fromTable Awhere(A.ID,A.SEQ)inch     (SelectId,seq fromTableGroup  byId,seq having Count(*)> 1)      androwID not inch(Select min(ROWID) fromTableGroup  byId,seq having Count(*)>1) --5. Find redundant duplicate records (multiple fields) in the table, not including the smallest ROWID records Select *  fromTable Awhere(A.ID,A.SEQ)inch     (SelectId,seq fromTableGroup  byId,seq having Count(*)> 1)      androwID not inch(Select min(ROWID) fromTableGroup  byId,seq having Count(*)>1)    --go to Heavy, cust_nbr,month primary key, CUST_NBR same, leave only month biggest recordDelete  fromOrders_tmp2where(CUST_NBR,Month) not inch (SelectCUST_NBR,Max(Month) Keep (Dense_rank firstOrder  by Month desc) Max_month fromORDERS_TMP2 TBGroup  byCUST_NBR)

Oracle de-weight