add databasetypename for time-with-time-zone

[gabor]

Is your feature request related to a problem? Please describe.
i'm writing code that makes decisions based on the https://pkg.go.dev/database/sql#ColumnType.DatabaseTypeName.
the problem is:

• for the postgres type time, it says TIME
• for the postgres type time with time zone, it says 1266

i can hardcode 1266 into my code, but i feel something like TIMETZ would be better.

Describe the solution you'd like
return something better than 1266 for time-with-time-zone

Describe alternatives you've considered
i can just use the value "1266" instead.

[jackc]

I suppose we could add some sort of support for it... But FYI, the PostgreSQL project itself recommends against using that type. From https://www.postgresql.org/docs/current/datatype-datetime.html:

The type time with time zone is defined by the SQL standard, but the definition exhibits properties which lead to questionable usefulness.

and later on the page

We do not recommend using the type time with time zone (though it is supported by PostgreSQL for legacy applications and for compliance with the SQL standard).

[gabor]

i see, thanks for the info. i still need to handle it in my use-case becaue of some legacy reasons, but i'll just go with the "1266". can i assume that that number will never change?

[jackc]

That number is the OID assigned to the type in PostgreSQL. That will never change. The only way that would change in pgx is if pgx added some sort of support for timetz - then the name would change to timetz. I don't have any plans to do that, but if someone submitted a PR that added some sort of meaningful support I guess it could happen.

But for now I have added TimetzOID and TimetzArrayOID constants to pgtype so at least you can use a named constant.