Oracle - Assigning the correct Date from a Set - sql

Question

I have a table A like below
REGID | PKG_DESC | EVENT_DATE | IS_CON | IS_REN
-----------------------------------------------------
1234 | cc | 27-MAR-14 | 0 | 0
1234 | cc | 27-JUN-14 | 1 | 0
1234 | GUI | 27-MAR-14 | 0 | 0
1234 | GUI | 27-JUN-14 | 1 | 0
1234 | GUI | 27-SEPT-14 | 0 | 1
1234 | GUI | 27-SEPT-15 | 0 | 1
1234 | REMOTE | 27-MAR-14 | 0 | 0
1234 | REMOTE | 27-JUN-14 | 1 | 0
1234 | REMOTE | 27-SEPT-14 | 0 | 1
2431 | cc | 27-MAR-14 | 0 | 0
2431 | cc | 27-JUN-14 | 1 | 0
I have a query like below
select a.reg_id, b.sess_start_dt,
case when TRUNC(A.EVENT_DATE) - B.SESS_START_DT BETWEEN 0-30 THEN 'DAYS 0_30'
WHEN TRUNC(A.EVENT_DATE) - B.SESS_START_DT BETWEEN 31-60 THEN 'DAYS 31-60'
from tab a inner join tab b on a.reg_id = b.reg_id and a.is_ren = 1
union
select a.reg_id, b.sess_start_dt,
case when TRUNC(A.EVENT_DATE) - B.SESS_START_DT BETWEEN 0-30 THEN 'DAYS 0_30'
WHEN TRUNC(A.EVENT_DATE) - B.SESS_START_DT BETWEEN 31-60 THEN 'DAYS 31-60'
from tab a inner join tab b on a.reg_id = b.reg_id and a.is_con = 1
Tab B contains all the usage for each reg_id there will be 100's of records.. Sample of few are
REGID | SESS_START_DT
1234 | 27-Jan-14
1234 | 20-MAR-12
1234 | 27-MAR-12
1234 | 01-sept-14
1234 | 07-sept-14
1234 | 29-JUL-14
1234 | 03-AUG-14
1234 | 27-MAR-13
1234 | 27-MAR-12
1234 | 27-MAR-12
1234 | 27-MAR-12
1234 | 27-MAR-12
1234 | 27-MAR-12
1234 | 27-MAR-12
2431 | 20-JUN-14
The Above query needs to be corrected in a way like,
1) If the REG_ID is having at least one is_ren = 1 then that subscription should be considered as renewal subscription and needs to get the 30 days and 60 days usage from table B from his is_ren = 1 event_date. (for REGID 1234 only is_ren query should execute)
2) If multiple IS_REN = 1 are existing for each REGID then the usage needs to be taken 30 days and 60 days from table B with the MIN(event_date). in this case the usage should be taken from 27-SEPT-14 instead of 27-SEPT-15
3) If there is no IS_REN = 1 and there is IS_CON = 1 then it's considered as conversion and usage should be taken before 60 days from the converted date (for REGID 2431, usage needs to get 60 days back from 27-JUN-14{this is my event_date in the query})
The O/P should be like
REGID | EVENT_DATE | DAYS 0_30 | DAYS 31-60 | CODE
1234 | 27-SEPT-14 | 2 | 2 | REN
2431 | 27-JUL-14 | 1 | 0 | CON

Answer 1

If my assumptions in my Comment are correct, this may be what you need. Notice the order by clause in row_number() - first the rows with is_ren = 1, then the rows with is_ren = 0 and is_con = 1, then all the other rows, and within each group order by event_date ascending. This way, the top row (rn = 1), which is the only one I use in the outer query, will have is_ren = 1 with the earliest possible date, or if no is_ren = 1 then the row with is_con = 1 and the earliest date, or else just the earliest date. (In the last case, the CODE will be null: this means there were no is_ren = 1 and no is_con = 1 for that regid.
Not sure why you have 27-JUL-14 in the output for regid = 2431, that should be 27-JUN-14. Also, there are no four-letter months in Oracle ("SEPT"). The output shows dates using my session parameters; if you need to format the dates, use to_date(event_date, .....) with the desired date format model. Also, since the data you provided is just dates (with no time-of-day component), I didn't truncate anything; you may need to, if your real data has time-of-day components.
with
table_a ( regid, pkg_desc, event_date, is_con, is_ren ) as (
select 1234, 'cc' , to_date ('27-MAR-14', 'dd-MON-rr'), 0, 0 from dual union all
select 1234, 'cc' , to_date ('27-JUN-14', 'dd-MON-rr'), 1, 0 from dual union all
select 1234, 'GUI' , to_date ('27-MAR-14', 'dd-MON-rr'), 0, 0 from dual union all
select 1234, 'GUI' , to_date ('27-JUN-14', 'dd-MON-rr'), 1, 0 from dual union all
select 1234, 'GUI' , to_date ('27-SEP-14', 'dd-MON-rr'), 0, 1 from dual union all
select 1234, 'GUI' , to_date ('27-SEP-15', 'dd-MON-rr'), 0, 1 from dual union all
select 1234, 'REMOTE', to_date ('27-MAR-14', 'dd-MON-rr'), 0, 0 from dual union all
select 1234, 'REMOTE', to_date ('27-JUN-14', 'dd-MON-rr'), 1, 0 from dual union all
select 1234, 'REMOTE', to_date ('27-SEP-14', 'dd-MON-rr'), 0, 1 from dual union all
select 2431, 'cc' , to_date ('27-MAR-14', 'dd-MON-rr'), 0, 0 from dual union all
select 2431, 'cc' , to_date ('27-JUN-14', 'dd-MON-rr'), 1, 0 from dual
),
table_b ( regid, sess_start_dt ) as (
select 1234, to_date ('27-JAN-14', 'dd-MON-rr') from dual union all
select 1234, to_date ('20-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('01-SEP-14', 'dd-MON-rr') from dual union all
select 1234, to_date ('07-SEP-14', 'dd-MON-rr') from dual union all
select 1234, to_date ('29-JUL-14', 'dd-MON-rr') from dual union all
select 1234, to_date ('03-AUG-14', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-13', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 1234, to_date ('27-MAR-12', 'dd-MON-rr') from dual union all
select 2431, to_date ('20-JUN-14', 'dd-MON-rr') from dual
),
prep ( regid, event_date, code, rn ) as (
select regid, event_date,
case when is_ren = 1 then 'REN' when is_con = 1 then 'CON' else null end,
row_number() over (partition by regid
order by case when is_ren = 1 then 0
when is_con = 1 then 1 else 2 end,
event_date)
from table_a
)
select p.regid, p.event_date,
count(case when b.sess_start_dt between p.event_date - 30 and p.event_date
then 1 end) as days_0_30,
count(case when b.sess_start_dt between p.event_date - 60 and p.event_date - 31
then 1 end) as days_31_60,
p.code
from prep p inner join table_b b on p.regid = b.regid
where rn = 1
group by p.regid, p.event_date, p.code
;
Output:
REGID EVENT_DATE DAYS_0_30 DAYS_31_60 COD
---------- ------------------- ---------- ---------- ---
1234 2014-09-27 00:00:00 2 2 REN
2431 2014-06-27 00:00:00 1 0 CON