Horton

Re: jsonpath: Inconsistency of timestamp_tz() Output

Junwang Zhao <zhjwpku@gmail.com>

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From: Junwang Zhao <zhjwpku@gmail.com>
To: "David E. Wheeler" <david@justatheory.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2024-07-09T15:08:52Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Fix comment in libpqrcv_check_conninfo().

  2. Remove useless extern keywords

On Tue, Jul 9, 2024 at 10:22 PM David E. Wheeler <david@justatheory.com> wrote:
>
> On Jul 9, 2024, at 10:07, David E. Wheeler <david@justatheory.com> wrote:
>
> > So perhaps I had things reversed before. Maybe it’s actually doing the right then when it converts a timestamp to a timestamptz, but not when it the input contains an offset, as in your example.
>
> To clarify, there’s an inconsistency in the output of timestamp_tz() depending on whether the input has an offset or not. With offset:
>
> david=# select jsonb_path_query_tz('"2024-08-15 12:34:56-05"', '$.timestamp_tz()');
>      jsonb_path_query_tz
> -----------------------------
>  "2024-08-15T12:34:56-05:00"
>
> And without:
>
> david=# select jsonb_path_query_tz('"2024-08-15 12:34:56"', '$.timestamp_tz()');
>      jsonb_path_query_tz
> -----------------------------
>  "2024-08-15T16:34:56+00:00"
>
> I suspect the latter is correct, given that the timestamptz type appears to be an int64, presumably always in UTC. I don’t understand where the first example stores the offset.

In JsonbValue.val.datatime, there is a tz field, I think that's where
the offset stored, it is 18000 in the first example

struct
{
  Datum value;
  Oid typid;
  int32 typmod;
  int tz; /* Numeric time zone, in seconds, for
            * TimestampTz data type */
} datetime;

>
> Best,
>
> David
>
>
>


-- 
Regards
Junwang Zhao