Calculate age as of end of pay period - oracle

Question

I have been tasked to calculate age based on date of birth as of end of every two weeks (pay period). Is that possible?
I can calculate as of sysdate but cant think of how I can achieve this task.
TO_CHAR(SYSDATE,'yyyy')-TO_CHAR(PAE.BIRTHDATE,'yyyy') > 50
Hire Date
Birth Date
Term Date
Employee Status
BSI Group
Age Years
Months
Days
04/05/2021
12/20/1971
01/01/1700
A1
50
49
3
13

Answer 1

When looking at your example
TO_CHAR(SYSDATE,'yyyy')-TO_CHAR(PAE.BIRTHDATE,'yyyy') > 50
it seems that you just want to know whether a person is over 50 years old
(there may be more age brackets).
You could use the ADD_MONTHS() function for just adding 600 months to the
individual DOB values, and then check whether this "calculated date" is after the payment date. The following queries are just a rough illustration.
Test data: person & DOB
-- person 100 will be 50 years old on 16 April 2021 -> must be in the "over 50" bracket thereafter
create table persondetails( id primary key, dob )
as
select 1, date '1955-01-01' from dual union all
select 2, date '1965-01-01' from dual union all
select 100, date '1971-04-16' from dual union all
select 3, date '1975-01-01' from dual union all
select 4, date '1985-01-01' from dual union all
select 5, date '1995-01-01' from dual union all
select 6, date '2005-01-01' from dual
;
-- sysdate ie today's date is: 2021-04-03
select id
, case
when add_months( dob, 600 ) > sysdate then 'under 50'
else 'over 50'
end age_bracket
from persondetails
;
ID AGE_BRACKET
1 over 50
2 over 50
100 under 50
3 under 50
4 under 50
5 under 50
6 under 50
Test data: paydates and payroll (every person gets paid on every "paydate")
-- payments every fortnight
create table paydates
as
select date '2021-02-12' + ( level * 14 ) paydate
from dual
connect by level <= 12 ;
create table payroll
as
select P1.id, P2.paydate
from (
select id from persondetails
) P1
cross join (
select paydate from paydates
) P2
;
View
create or replace view paa -- payment dates and age
as
select P1.id
, P1.dob
, P2.paydate
, case
when add_months( P1.dob, 600 ) > P2.paydate then 'under 50'
else 'over 50'
end age_bracket
from persondetails P1 join payroll P2 on P1.id = P2.id
;
Final query & result
select * from paa where id = 100 order by paydate ;
ID DOB PAYDATE AGE_BRACKET
100 16-APR-71 26-FEB-21 under 50
100 16-APR-71 12-MAR-21 under 50
100 16-APR-71 26-MAR-21 under 50
100 16-APR-71 09-APR-21 under 50
100 16-APR-71 23-APR-21 over 50
100 16-APR-71 07-MAY-21 over 50
100 16-APR-71 21-MAY-21 over 50
100 16-APR-71 04-JUN-21 over 50
100 16-APR-71 18-JUN-21 over 50
100 16-APR-71 02-JUL-21 over 50
100 16-APR-71 16-JUL-21 over 50
100 16-APR-71 30-JUL-21 over 50
DBfiddle
ADDENDUM
In an Oracle Community discussion, user Blue Shadow has posted a solution for the "Years Months Days" problem (under "Accepted Answer"):
> select c_start_date, c_end_date
> ,trunc(months_between(c_end_date, c_start_date) / 12) as yrs
> ,trunc(mod(months_between(c_end_date, c_start_date), 12)) as mnths
> ,trunc(c_end_date - add_months(c_start_date, trunc(months_between(c_end_date, c_start_date)))) as dys from t
You can add this to the "view code", and get the years/months/days values. Example see dbfiddle.
-- eg results for id 100
ID DOB PAYDATE AGE_BRACKET YRS MNTHS DYS
100 16-APR-71 26-FEB-21 under 50 49 10 10
100 16-APR-71 12-MAR-21 under 50 49 10 24
100 16-APR-71 26-MAR-21 under 50 49 11 10
100 16-APR-71 09-APR-21 under 50 49 11 24
100 16-APR-71 23-APR-21 over 50 50 0 7
100 16-APR-71 07-MAY-21 over 50 50 0 21
100 16-APR-71 21-MAY-21 over 50 50 1 5
100 16-APR-71 04-JUN-21 over 50 50 1 19