Message-ID: <gh-pgjdbc-pgjdbc-2311-c2945598242@github.com>
From: "davecramer (@davecramer)" <noreply+davecramer@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Thu, 05 Jun 2025 18:23:45 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #2311: Why is client time zone not configurable?
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> > How would we know the correct TZ ?
> 
> For that option, the JDBC driver would have to hard-code time zones with known name changes, and try one after the other. (Yes, quite ugly.)
Very ugly
> 
> > Well changing the TZ will change the result of getTimestamp. The server changes the time based on the session TZ. It does not store TZ in the data.
> 
> The java.sql.Timestamp instance is created by the JDBC driver, no? So if the JDBC driver connects to the server with connection parameter TimeZone=GMT, I'd imagine the JDBC driver would receive the timestamp at GMT/UTC, but then convert it to the local JDK time zone for the purposes of creating the java.sql.Timestamp object (when working with `timestamptz` values). That way, the change to TimeZone=GMT can be regarded as a JDBC driver implementation detail that does not change the semantics of getTimestamp(). (But as [@vlsi](https://github.com/vlsi) pointed out it would still change the string representation of `timestamptz` when casted to `text`.)

What happens to data that the driver did not create ?

Dave