SQL Query to retrieve one line from duplicate records

Question

Hi
I have one table which contains duplicate records in multiple column but the difference is in one column which contains the value 0 or positive. The query i want is to retrieve only the line with the positive value for only the duplicated records.
here below a sample data for your reference:
CREATE TABLE TRANS
  CALLTRANSTYPE     NVARCHAR2(6),
  ORIGANI                 NVARCHAR2(40),
  TERMANI                 NVARCHAR2(40),
  STARTTIME               DATE,
  STOPTIME                DATE,
  CELLID                  NVARCHAR2(10),
  CONNECTSECONDS          NUMBER,
  SWITCHCALLCHARGE        NUMBER
INSERT INTO TRANS VALUES ('REC','555988801','222242850',to_date('05/15/2012 09:15:00','mm/dd/yyyy hh24:mi:ss'),to_date('05/15/2012 09:15:25','mm/dd/yyyy hh24:mi:ss'),null,25,0)
INSERT INTO TRANS VALUES ('REC','555988801','222242850',to_date('05/15/2012 09:15:00','mm/dd/yyyy hh24:mi:ss'),to_date('05/15/2012 09:15:25','mm/dd/yyyy hh24:mi:ss'),null,25,18000)
INSERT INTO TRANS VALUES ('REC','555988801','222242850',to_date('05/15/2012 09:18:03','mm/dd/yyyy hh24:mi:ss'),to_date('05/15/2012 09:18:20','mm/dd/yyyy hh24:mi:ss'),null,17,0)
The output i want to have is:
CALLTRANSTYPE     ORIGANI          TERMANI          STARTTIME          STOPTIME          CELLID          CONNECTSECONDS          SWITCHCALLCHARGE
REC          555988801     222242850     05/15/2012 09:15:00     05/15/2012 09:15:25               25               18000
REC          555988801     222242850     05/15/2012 09:18:03     05/15/2012 09:18:20               17               0 Thank you.

Answer 1

Hi ekh
this is the query i want to have, thank you for the help:
SQL> Select *from
select CALLTRANSTYPE,ORIGANI,TERMANI,STARTTIME,STOPTIME,CELLID,CONNECTSECONDS,SWITCHCALLCHARGE
,row_number() over( partition by     STARTTIME    ,STOPTIME order by    SWITCHCALLCHARGE DESC     ) rn from TRANS
where rn=1;  
CALLTR ORIGANI                                  TERMANI                                  STARTTIME STOPTIME  CELLID     CONNECTSECONDS SWITCHCALLCHARGE     RN
REC    555988801                                222242850                                15-MAY-12 15-MAY-12                        25            18000      1
REC    555988801                                222242850                                15-MAY-12 15-MAY-12                        17                0      1Regrads
Lucienot.