SQL to get unique record

Question

EVENT_ID TRANSFER_ID
44745 693420
44744 693420
44743 603420
44742 603420
44741 543420
44740 543420
44739 543421
44738 543421
How can I get list of unique TRANSFER_ID?
EVENT_ID TRANSFER_ID
44745 693420
44743 603420
44741 543420
44739 543421

Answer 1

Maybe you'd be better of pivoting your data first and use Frank's approach on the result
NOT TESTED !
with
the_data(event_id,the_key,the_value) as
(select 44745,'transfer.id','693420' from dual union all
select 44745,'transfer.user','ABC' from dual union all
select 44744,'transfer.id','693420' from dual union all
select 44744,'transfer.user','DEF' from dual union all
select 44743,'transfer.id','603420 ' from dual union all
select 44743,'transfer.user','GHI' from dual union all
select 44742,'transfer.id','603420' from dual union all
select 44742,'transfer.user','JKL' from dual union all
select 44741,'transfer.id','543420' from dual union all
select 44741,'transfer.user','MNO' from dual union all
select 44740,'transfer.id','543420' from dual union all
select 44740,'transfer.user','PQR' from dual union all
select 44739,'transfer.id','543421 ' from dual union all
select 44739,'transfer.user','STU' from dual union all
select 44738,'transfer.id','543421' from dual union all
select 44738,'transfer.user','VWX' from dual
select event_id,
       max(decode(the_key,'transfer.id',the_value)) transfer_id,
       max(decode(the_key,'transfer.user',the_value)) transfer_user
  from the_data
group by event_idYou could use PIVOT ... but no Database version was specified
Regards
Etbin