TO_TIMESTAMP in Postgresql dialect differs from definition

I have written a nice query in Postgresql that converts a number of seconds into a timestamp with timezone, for example something like this:

SELECT TO_TIMESTAMP(1284352323);

This should result in a value of 2010-09-13 04:32:03+00.

Unfortunately the definition within the Postgresql Dialect, here h2/src/main/org/h2/mode/FunctionsPostgreSQL.java, expects 2 parameters, and will convert the (optional) first using the format specified in the second parameter to parse it.

I can't find any documentation on the Postgresql site, where the TO_TIMESTAMP function ever worked that way. Do enlighten me if I have missed that.

This is what I can find on https://www.postgresql.org/docs/14/functions-datetime.html:

 to_timestamp ( double precision ) → timestamp with time zone
Convert Unix epoch (seconds since 1970-01-01 00:00:00+00) to timestamp with time zone
to_timestamp(1284352323) → 2010-09-13 04:32:03+00

Should I look at making a PR for this change?

Cheers,
Bas de Wit

Inspect h2/src/main/org/h2/mode/FunctionsPostgreSQL.java and the TO_TIMESTAMP handling first. Verify the PostgreSQL one-argument Unix-epoch behavior with the query shown; done means the dialect accepts that form and returns the documented timestamp-with-time-zone result.