Last day of last completed quarter

Does this work?

dbadmin=> SELECT current_date today, (TRUNC(current_date, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-09-30
(1 row)

dbadmin=> SELECT current_date today, (TRUNC('05/21/2021'::DATE, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-03-31
(1 row)

@Jim_Knicely said:
Does this work?

dbadmin=> SELECT current_date today, (TRUNC(current_date, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-09-30
(1 row)

dbadmin=> SELECT current_date today, (TRUNC('05/21/2021'::DATE, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-03-31
(1 row)

This should work for all quarters except Q1

If today's date is 01/12/2022, then i don't think above logic would work since it would basically do 1-1> 01/12/2022 is Q1 so 1 in numerical value. Makes sense?

This isn't right?

dbadmin=> SELECT current_date today, (TRUNC('01/12/2022'::DATE, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-12-31
(1 row)

@Jim_Knicely said:
This isn't right?

dbadmin=> SELECT current_date today, (TRUNC('01/12/2022'::DATE, 'Q')-1)::DATE last_day_of_qtr;
   today    | last_day_of_qtr
------------+-----------------
 2021-11-16 | 2021-12-31
(1 row)

this works, i read it wrong - we're doing minus 1 of first day of quarter. thank you!