Why sequel connection sets timezone to UTC?

[wuarmin]

Hello,

my postgresql server has the time zone Europe/Vienna:

my_app=# RESET timezone; SHOW timezone;
RESET
Time: 0.284 ms
   TimeZone    
---------------
 Europe/Vienna
(1 row)

Time: 0.116 ms

But if I connect with my ruby app:

my_app[development]> my_db = Sequel.connect('postgres://my_app:hu8jmn3@database/my_app_db?search_path=public')
=> #<Sequel::Postgres::Database host=database database=doc_park user=doc_park_user>
my_app[development]> my_db.fetch("show time zone").to_a
=> [{TimeZone: "Etc/UTC"}]
my_app[development]> my_db.fetch("select current_timestamp").to_a
=> [{current_timestamp: 2025-06-04 10:54:25.416643 +0000}]
my_app[development]> 

I get UTC. Can someone explain this? I would have expected, if not explicitly configured, that the time zone from the db-server would be used.

thanks!

[jeremyevans]

This must be related to your environment, it isn't something Sequel does by default:

$ bin/sequel -E postgres:///?user=sequel_test -c "p DB.fetch('show time zone').to_a; p DB.get(Sequel::CURRENT_TIMESTAMP)" 
2025-06-04 07:30:19 INFO: (0.000393s) SET standard_conforming_strings = ON
2025-06-04 07:30:19 INFO: (0.000089s) SET client_min_messages = 'WARNING'
2025-06-04 07:30:19 INFO: (0.000079s) SET DateStyle = 'ISO'
2025-06-04 07:30:19 INFO: (0.000161s) show time zone
[{TimeZone: "US/Pacific"}]
2025-06-04 07:30:19 INFO: (0.000625s) SELECT CAST(current_setting('server_version_num') AS integer) AS v
2025-06-04 07:30:19 INFO: (0.000170s) SELECT CURRENT_TIMESTAMP AS "v" LIMIT 1
2025-06-04 07:30:19.833317 -0700

[wuarmin]

Ok, that's strange.
My OS has the correct time zone

user@ccf85cfd4628:~/app$ date
Wed Jun  4 17:10:31 CEST 2025

like ruby

irb(main):001> Time.now
=> 2025-06-04 17:11:50.868072094 +0200
irb(main):002> Time.now.zone
=> "CEST"

but not sequel:

sequel -E postgres://db_user:hu8jmn3@database/my_db?search_path=public -c "p DB.fetch('show time zone').to_a; p DB.get(Sequel::CURRENT_TIMESTAMP)"
2025-06-04 17:15:27 INFO: (0.000149s) SET standard_conforming_strings = ON
2025-06-04 17:15:27 INFO: (0.000095s) SET client_min_messages = 'WARNING'
2025-06-04 17:15:27 INFO: (0.000103s) SET search_path = "public"
2025-06-04 17:15:27 INFO: (0.000094s) SET DateStyle = 'ISO'
2025-06-04 17:15:27 INFO: (0.000117s) show time zone
[{TimeZone: "Etc/UTC"}]
2025-06-04 17:15:27 INFO: (0.000188s) SELECT CAST(current_setting('server_version_num') AS integer) AS v
2025-06-04 17:15:27 INFO: (0.000070s) SELECT CURRENT_TIMESTAMP AS "v" LIMIT 1
2025-06-04 15:15:27.622485 +0000

[wuarmin]

I found a timezone = 'Etc/UTC' setting in /var/lib/postgresql/data/postgresql.conf. That's the reason for the confusion.