Turn days into weeks, months, years.ORACLE - sql

Question

I have this query and result:
SQL> select AVG(SYSDATE - DOB) AS AVERAGE_AGE_IN_DAYS
2 FROM MORTAL;
AVERAGE_AGE_IN_DAYS
-------------------
17877.44
Is there a way to convert this to years, months, and days, within the same query?

Answer 1

To get the number of months you could use months_between
SELECT select AVG(months_between(SYSDATE,DOB)) AS AVERAGE_AGE_IN_MONTHS
For years, just do months_between/12
SELECT select AVG(months_between(SYSDATE,DOB)/12) AS AVERAGE_AGE_IN_YEARS
For weeks, i would just take your result for days and divide it by 7.
You might have to handle the results to fit your needs, but i think this should cover it.

Answer 2

How about:
select
floor(months_between(SYSDATE,DOB)/12) AS years,
trunc( months_between(SYSDATE,DOB) ) AS months,
SYSDATE - add_months( SYSDATE, trunc(months_between(SYSDATE,DOB)) ) AS days
This is years,months,days as the detail suggests. The title said weeks too but I'm not if you actually want them.

Answer 3

Perhaps your query would be:
with dates as (select AVG(SYSDATE - DOB) as d --average_in_days
from MORTAL
)
select trunc(d/365) as years
, trunc((d/365 - trunc(d/365)) * 12 ) as months
, trunc((((d/365 - trunc(d/365)) * 12) - trunc((d/365 - trunc(d/365)) * 12 )) * 4.348214) as weeks
, trunc(((((d/365 - trunc(d/365)) * 12) - trunc((d/365 - trunc(d/365)) * 12 )) * 4.348214
- trunc((((d/365 - trunc(d/365)) * 12) - trunc((d/365 - trunc(d/365)) * 12 )) * 4.348214 )
) * 7
) as days
from dates;

Answer 4

CREATE FUNCTION time_spell(p_days VARCHAR2) RETURN VARCHAR2 IS
v_y NUMBER;
v_yd NUMBER;
v_m NUMBER;
v_md NUMBER;
v_d NUMBER;
v_w NUMBER;
v_wd NUMBER;
v_days NUMBER;
v_yi NUMBER;
v_mi NUMBER;
v_wi NUMBER;
BEGIN
SELECT p_days/365 INTO v_y FROM dual;
if v_y not like '%.%' then
SELECT trunc(v_y) INTO v_yi FROM dual;
select substr(v_y||'.0',(select instr(v_y||'.0','.') from dual)) INTO v_yd from dual;
SELECT v_yd * 12 INTO v_m FROM dual;
SELECT trunc(v_m) INTO v_mi FROM dual;
select substr(v_m,(select instr(v_m,'.') from dual)) INTO v_md from dual;
SELECT v_md * 30 INTO v_d FROM dual;
SELECT v_d / 7 INTO v_w FROM dual;
SELECT trunc(v_w) INTO v_wi FROM dual;
select substr(v_w,(select instr(v_w,'.') from dual)) INTO v_wd from dual;
SELECT round(v_wd * 7) INTO v_days FROM dual;
RETURN v_yi||' Year(s) '||v_mi||' Month(s) '||v_wi||' Week(s) '||v_days||' Day(s) ';
else
SELECT trunc(v_y) INTO v_yi FROM dual;
select substr(v_y,(select instr(v_y,'.') from dual)) INTO v_yd from dual;
SELECT v_yd * 12 INTO v_m FROM dual;
SELECT trunc(v_m) INTO v_mi FROM dual;
select substr(v_m,(select instr(v_m,'.') from dual)) INTO v_md from dual;
SELECT v_md * 30 INTO v_d FROM dual;
SELECT v_d / 7 INTO v_w FROM dual;
SELECT trunc(v_w) INTO v_wi FROM dual;
select substr(v_w,(select instr(v_w,'.') from dual)) INTO v_wd from dual;
SELECT round(v_wd * 7) INTO v_days FROM dual;
RETURN v_yi||' Year(s) '||v_mi||' Month(s) '||v_wi||' Week(s) '||v_days||' Day(s) ';
end if;
END;
SELECT time_spell(17877.44) FROM dual;