unknown PostgreSQL timezone: 'Europe/Berlin'; will use UTC when select any data with timestamptz datatype on Windows

[sharmankin]

when I try make select any data with timestamptz datatype on Windows I get the warning (no exception)
unknown PostgreSQL timezone: 'Europe/Berlin'; will use UTC

For Example:

from psycopg import connect

conn = connect(
    '***********************************'
)
conn.execute(
    """
    set timezone to 'Europe/Berlin';
    """
)

cur = conn.cursor()
cur.execute(
    """
    select current_timestamp
    """
)

print(cur.fetchone())
# unknown PostgreSQL timezone: 'Europe/Berlin'; will use UTC
# (datetime.datetime(2022, 2, 9, 17, 5, 15, 614415, tzinfo=datetime.timezone.utc),)

and realy all data fetched from cursor in UTC

I check this on Linux and lib work properly without warnings

psycopg 3.0.8
python 3.9 - 3.10
Windows 11

[dvarrazzo]

The problem is caused by the fact that Windows doesn't have a system timezone database. For a description of why it's needed you can read this ramble.

I read here that the tzdata package allows to install the timezone db on Windows. If you install that package, is the problem solved? If so we can make it a psycopg dependency on windows.

[sharmankin]

Thanks a lot. Installing the tzdata library solved the problem. Thanks a lot for the quick response. The 3rd version of your library is much more convenient. Thanks again

[dvarrazzo]

No worries, thank you for testing. We will include the dependency starting from the next psycopg 3.0.9.