Thread: [GENERAL] Timezone locale consistency for functional indexes
I have a table that I try create an functional index on like this:
CREATE INDEX my_index_name
ON opening_hours (
opening_hours_type,
EXTRACT(YEAR FROM date),
EXTRACT(MONTH FROM date)
)
But I get the following error: functions in index expression must be
marked IMMUTABLE
But if I change it to:
CREATE INDEX my_index_name
ON opening_hours (
opening_hours_type,
EXTRACT(YEAR FROM date AT TIME ZONE 'UTC'),
EXTRACT(MONTH FROM date AT TIME ZONE 'UTC')
)
The index will be created.
On other systems it could be the oppsite, that it only works without
the additional AT TIME ZONE
On all systems, the default Timezone in postgresql.conf is set to UTC
and show timezone; return UTC. Additionally show lc_time; returns
nb_NO.UTF-8
What kind of system settings could cause this behaviour? We run
Ubuntu Linux 16.04 and Postgresql 9.6
Another question is, should I just create immutable functions wrappers
for this instead?
--
Kind Regards / Med Vennlig Hilsen
Olav Grønås Gjerde
I figured out the issue, it was as simple as some developers used the default in Java's Hibernate which created the timestamp columns without time zone. Anyway I guess this is the correct approach that also take summer time into consideration? And using the immutable function wrapper is wrong? On Mon, Jun 12, 2017 at 2:25 PM, Olav Gjerde <olav@backupbay.com> wrote: > I have a table that I try create an functional index on like this: > > CREATE INDEX my_index_name > ON opening_hours ( > opening_hours_type, > EXTRACT(YEAR FROM date), > EXTRACT(MONTH FROM date) > ) > > But I get the following error: functions in index expression must be > marked IMMUTABLE > > > But if I change it to: > > CREATE INDEX my_index_name > ON opening_hours ( > opening_hours_type, > EXTRACT(YEAR FROM date AT TIME ZONE 'UTC'), > EXTRACT(MONTH FROM date AT TIME ZONE 'UTC') > ) > The index will be created. > > On other systems it could be the oppsite, that it only works without > the additional AT TIME ZONE > > On all systems, the default Timezone in postgresql.conf is set to UTC > and show timezone; return UTC. Additionally show lc_time; returns > nb_NO.UTF-8 > > What kind of system settings could cause this behaviour? We run > Ubuntu Linux 16.04 and Postgresql 9.6 > > Another question is, should I just create immutable functions wrappers > for this instead? > > > -- > Kind Regards / Med Vennlig Hilsen > > Olav Grønås Gjerde -- Kind Regards / Med Vennlig Hilsen Olav Grønås Gjerde BackupBay Gjerde Asalvegen 19 4051 SOLA Norway Phone: +47 918 000 59
On 06/12/2017 06:11 AM, Olav Gjerde wrote: > I figured out the issue, it was as simple as some developers used the > default in Java's Hibernate which created the timestamp columns > without time zone. > > Anyway I guess this is the correct approach that also take summer time > into consideration? And using the immutable function wrapper is wrong? > > On Mon, Jun 12, 2017 at 2:25 PM, Olav Gjerde <olav@backupbay.com> wrote: >> I have a table that I try create an functional index on like this: >> >> CREATE INDEX my_index_name >> ON opening_hours ( >> opening_hours_type, >> EXTRACT(YEAR FROM date), >> EXTRACT(MONTH FROM date) >> ) >> >> But I get the following error: functions in index expression must be >> marked IMMUTABLE >> >> >> But if I change it to: >> >> CREATE INDEX my_index_name >> ON opening_hours ( >> opening_hours_type, >> EXTRACT(YEAR FROM date AT TIME ZONE 'UTC'), >> EXTRACT(MONTH FROM date AT TIME ZONE 'UTC') >> ) >> The index will be created. >> >> On other systems it could be the oppsite, that it only works without >> the additional AT TIME ZONE >> >> On all systems, the default Timezone in postgresql.conf is set to UTC >> and show timezone; return UTC. Additionally show lc_time; returns >> nb_NO.UTF-8 >> >> What kind of system settings could cause this behaviour? We run >> Ubuntu Linux 16.04 and Postgresql 9.6 >> >> Another question is, should I just create immutable functions wrappers >> for this instead? >> >> >> -- >> Kind Regards / Med Vennlig Hilsen >> >> Olav Grønås Gjerde > > > -- Adrian Klaver adrian.klaver@aklaver.com
On 06/12/2017 06:11 AM, Olav Gjerde wrote: Oops sent previous post before actual reply. > I figured out the issue, it was as simple as some developers used the > default in Java's Hibernate which created the timestamp columns > without time zone. > > Anyway I guess this is the correct approach that also take summer time > into consideration? And using the immutable function wrapper is wrong? > By correct approach, you mean setting timezone to 'UTC'? If by immutable function wrapper, you mean faking the immutability of a function, then yes I would see that as wrong. -- Adrian Klaver adrian.klaver@aklaver.com