How to caluclate tat between two dates of one timestamp field

Question

Hi,
could some one help how to caluclate days between two dates of single timestamp filed and with this
query
Select * from m_activity_transaction where actn_opp_id in (
Select actn_opp_id from m_activity_transaction where ACTN_ACTV_ID = 218
Group by actn_opp_id
having count(*) > 1 ) and ACTN_ACTV_ID = 218
order by actn_performed_on
iam getting output is
ACTN_ID ACTN_OPP_ID ACTN_PERFORMED_ON
319415 95831 27-JAN-12 11.06.20.000000 AM
315249 95831 08-FEB-12 05.32.54.000000 PM
301927 103509 20-DEC-11 04.01.43.000000 PM
301458 103509 19-DEC-11 04.51.03.000000 PM
294841 115840 10-JAN-12 03.20.12.000000 PM
312062 115840 11-JAN-12 05.17.06.000000 PM
and i nedd to caluclate no.of days between two dates like 27-JAN-12 11.06.20.000000 AM and 08-FEB-12 05.32.54.000000 PM where actn_id is unique AND ACTN_OPP_ID IS NOT UNIQUE.
Thanks in Advance,
vvr.

Answer 1

This way?
with data as
select 315249 a, 95831 b, to_timestamp('27-JAN-12 11.06.20.000000 AM', 'DD-MON-RR HH.MI.SS.FF6 AM') dt from dual union all
select 319415, 95831, to_timestamp('08-FEB-12 05.32.54.000000 PM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual union all
select 301927, 103509 , to_timestamp('20-DEC-11 04.51.03.000000 PM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual union all
select 301458 , 103509 , to_timestamp('19-DEC-11 04.01.43.000000 PM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual union all
select 363810 , 144656 , to_timestamp('27-JUN-12 12.43.28.000000 PM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual union all
select 363500 , 144656 , to_timestamp('26-JUN-12 11.41.50.000000 AM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual union all
select 363354 , 144656 , to_timestamp('25-JUN-12 12.41.13.000000 PM', 'DD-MON-RR HH.MI.SS.FF6 AM') from dual
select a, b, diff
  from (
        select a, b, extract( day from (dt - lag(dt) over (partition by b order by dt, a)) ) diff
          from data
       ) tab
where tab.diff is not null;
A                      B                      DIFF                  
319415                 95831                  12                    
301927                 103509                 1                     
363500                 144656                 0                     
363810                 144656                 1