Re: is there an immutable function to switch from date to character?

[Steve Baldwin <steve.baldwin@xxxxxxxxx>]

On Thu, Apr 25, 2024 at 7:31 AM Celia McInnis <celia.mcinnis@xxxxxxxxx> wrote:

create temporary table junk as select now()::date as evtdate;

alter table junk add column chardate text GENERATED ALWAYS AS (to_char(evtdate,'YYYY-Mon-DD')) STORED;

ERROR:  generation _expression_ is not immutable

Maybe this is a hack but..

b2bcreditonline=# create temporary table junk as select now()::date as evtdate;
SELECT 1
b2bcreditonline=# alter table junk add column chardate text GENERATED ALWAYS AS (to_char(evtdate,'YYYY-Mon-DD')) STORED;
ERROR:  generation _expression_ is not immutable
b2bcreditonline=# create or replace function date_to_text(i_date in date) returns text immutable language sql as $$ select to_char(i_date, 'YYYY-MM-DD') $$;
CREATE FUNCTION
b2bcreditonline=# alter table junk add column chardate text GENERATED ALWAYS AS (date_to_text(evtdate)) STORED;
ALTER TABLE
b2bcreditonline=# select * from junk;
  evtdate   |  chardate
------------+------------
 2024-04-24 | 2024-04-24
(1 row)