On 12-1-2017 15:09, Tim Ward tdw@... [firebird-support] wrote:

> Sorry if this is a really basic question, but some time spent searching
> has failed to find for me the definitive detailed documentation on
> exactly how Firebird handles time zones (I'm particularly interested, to
> start with, in using CURRENT_TIMESTAMP to create a value in a TIMESTAMP
> field, and later reading it out and using it to display in a UI, but
> that's only to start with).
>
> Can someone point me in the right direction please?
>

Basically, Firebird doesn't really do anything with time zones, Firebird
uses the timezone of the server for current_timestamp, current_time and
current_date (and 'today' and 'now'). Timestamps (etc) in Firebird have
no time zone information, so it is not possible to distinguish between
say today 12:00 in UTC or UTC+1. This is important to realize if you
access or write dates from systems in another time zone.

For example the JDBC specification requires that times are handled in
the timezone of the JVM, so if Firebird server is in UTC and the JVM is
in UTC+1 you will get discrepancies when using `current_timestamp` in
Firebird and things like `LocalDate.now()` on the Java side.

PS In the future, could you start a new message instead of replying to
an existing thread. In my mail client this message is grouped under the
"FB 2.5 migrate to 3.0" thread instead of its own.

--
Mark Rotteveel