Re: Adding timestamp column

Am 03.09.25 um 17:50 schrieb Mauricio Fernandez:
> Hi admins, greetings.
>
> I'm trying to add a timestamp column in an existent table.
>
> This query works fine:
>
> select timecreated, timezone('America/Santiago'::text,
> to_timestamp(timecreated::double precision)) datecreated
> from MDL_LOGSTORE_STANDARD_LOG;
>
> But, when I want to alter the table I get  a syntax error
>
> alter table MDL_LOGSTORE_STANDARD_LOG
>   add column datecreated timestamp
>   generated always as ( timezone ('America/Santiago'::text,
> to_timestamp(timecreated::double precision)));
>
> SQL Error [42601]: ERROR: syntax error at end of input
>   Position: 185
>
> I would appreciate some tips
>
> Thanks in advanced
>
> kind regards
>
> Mauricio Fernández

Instead of

alter table MDL_LOGSTORE_STANDARD_LOG
  add column datecreated timestamp
  generated always as ( timezone ('America/Santiago'::text,
to_timestamp(timecreated::double precision)));

I would suggest

ALTER TABLE MDL_LOGSTORE_STANDARD_LOG
ADD COLUMN datecreated TIMESTAMP
  GENERATED ALWAYS AS (timecreated AT TIME ZONE 'America/Santiago') STORED;

You didn't tell us the data type of the column timecreated. It should be
'TIMESTAMPTZ DEFAULT current_timestamp' for it to work properly.

As of Version 18 you can leave out STORED, creating a virtual generated
column.

Kind Regards,

Holger

--

Holger Jakobs, Bergisch Gladbach