Sì; utilizzando LEAD() funzione analitica, puoi calcolare l'effdt successivo nelle tabelle dei lavori e dei benefit, il che semplifica l'interrogazione tra gli intervalli.
Qualcosa come:
with dates as (select trunc(sysdate, 'yyyy') - 1 + level the_date,
to_number(to_char(trunc(sysdate, 'yyyy') - 1 + level, 'mm')) monthofyear,
to_number(to_char(sysdate, 'yyyy')) calendar_year
from dual
connect by level <= 365),
jobs as (select 123 emplid, to_date('01/02/2015', 'dd/mm/yyyy') effdt, 900 deptid, 'A' hr_status from dual union all
select 123 emplid, to_date('30/06/2015', 'dd/mm/yyyy') effdt, 900 deptid, 'I' hr_status from dual union all
select 123 emplid, to_date('01/08/2015', 'dd/mm/yyyy') effdt, 901 deptid, 'A' hr_status from dual),
benefits as (select 123 emplid, to_date('01/03/2015', 'dd/mm/yyyy') effdt, 'PPO' benefit_plan, 'A' status from dual union all
select 123 emplid, to_date('31/07/2015', 'dd/mm/yyyy') effdt, null benefit_plan, 'I' status from dual union all
select 123 emplid, to_date('01/09/2015', 'dd/mm/yyyy') effdt, 'HMO' benefit_plan, 'A' status from dual),
-- ********* end of mimicking your tables ********* --
j as (select emplid,
effdt,
deptid,
hr_status,
lead(effdt, 1, sysdate) over (partition by emplid order by effdt) next_effdt
from jobs),
b as (select emplid,
effdt,
benefit_plan,
status,
lead(effdt, 1, sysdate) over (partition by emplid order by effdt) next_effdt
from benefits)
select distinct j.emplid,
d.calendar_year,
d.monthofyear,
j.deptid,
b.benefit_plan
from j
inner join dates d on (d.the_date >= j.effdt and d.the_date < j.next_effdt)
inner join b on (j.emplid = b.emplid)
where d.the_date <= sysdate
and d.the_date between to_date (:year_prompt || '01-01', 'YYYY-MM-DD')
and to_date (:year_prompt || '12-31', 'YYYY-MM-DD') -- if no index on d.the_date, maybe use trunc(the_date, 'yyyy') = :year_prompt
and b.status = 'A'
and d.the_date between b.effdt and b.next_effdt
order by 1, 4, 2, 3;
EMPLID CALENDAR_YEAR MONTHOFYEAR DEPTID BENEFIT_PLAN
---------- ------------- ----------- ---------- ------------
123 2015 3 900 PPO
123 2015 4 900 PPO
123 2015 5 900 PPO
123 2015 6 900 PPO
123 2015 7 900 PPO
123 2015 9 901 HMO
123 2015 10 901 HMO
123 2015 11 901 HMO
(Ovviamente, puoi escludere le dates , jobs e benefits sottoquery dalla query precedente, poiché hai già quelle tabelle. Sono presenti nella query solo per simulare la presenza di tabelle con quei dati senza che sia necessario creare effettivamente le tabelle.).
ETA:ecco una versione che calcola solo i 12 mesi in base all'anno trascorso, che riduce le righe della data a 12, anziché 365/366 righe.
Sfortunatamente, avrai ancora bisogno del distinto, per tenere conto di quando hai più righe a partire dallo stesso mese.
Ad esempio, con i dati nell'esempio seguente, ti ritroveresti con 3 righe per il mese 6 se rimuovessi il distinto. Tuttavia, il numero di righe su cui sta operando il distinto sarà molto inferiore rispetto a prima.
with dates as (select add_months(to_date(:year_prompt || '-01-01', 'YYYY-MM-DD'), - 1 + level) the_date,
level monthofyear,
:year_prompt calendar_year -- assuming this is a number
from dual
connect by level <= 12),
jobs as (select 123 emplid, to_date('01/02/2015', 'dd/mm/yyyy') effdt, 900 deptid, 'A' hr_status from dual union all
select 123 emplid, to_date('15/06/2015', 'dd/mm/yyyy') effdt, 900 deptid, 'I' hr_status from dual union all
select 123 emplid, to_date('26/06/2015', 'dd/mm/yyyy') effdt, 900 deptid, 'A' hr_status from dual union all
select 123 emplid, to_date('01/08/2015', 'dd/mm/yyyy') effdt, 901 deptid, 'A' hr_status from dual),
benefits as (select 123 emplid, to_date('01/03/2015', 'dd/mm/yyyy') effdt, 'PPO' benefit_plan, 'A' status from dual union all
select 123 emplid, to_date('31/07/2015', 'dd/mm/yyyy') effdt, null benefit_plan, 'I' status from dual union all
select 123 emplid, to_date('01/09/2015', 'dd/mm/yyyy') effdt, 'HMO' benefit_plan, 'A' status from dual),
-- ********* end of mimicking your tables ********* --
j as (select emplid,
trunc(effdt, 'mm') effdt,
deptid,
hr_status,
trunc(coalesce(lead(effdt) over (partition by emplid order by effdt) -1, sysdate), 'mm') end_effdt
-- subtracting 1 from the lead(effdt) since here since the original sql had d.the_date < j.next_effdt and we need
-- to take into account when the next_effdt is the first of the month; we want the previous month to be displayed
from jobs),
b as (select emplid,
trunc(effdt, 'mm') effdt,
benefit_plan,
status,
trunc(lead(effdt, 1, sysdate) over (partition by emplid order by effdt), 'mm') end_effdt
from benefits)
select distinct j.emplid,
d.calendar_year,
d.monthofyear,
j.deptid,
b.benefit_plan
from j
inner join dates d on (d.the_date between j.effdt and j.end_effdt)
inner join b on (j.emplid = b.emplid)
where d.the_date <= sysdate
and b.status = 'A'
and d.the_date between b.effdt and b.end_effdt
order by 1, 4, 2, 3;
EMPLID CALENDAR_YEAR MONTHOFYEAR DEPTID BENEFIT_PLAN
---------- ------------- ----------- ---------- --------------------------------
123 2015 3 900 PPO
123 2015 4 900 PPO
123 2015 5 900 PPO
123 2015 6 900 PPO
123 2015 6 900 PPO
123 2015 7 900 PPO
123 2015 9 901 HMO
123 2015 10 901 HMO
123 2015 11 901 HMO
