Re: Type OIDs

* Tom Lane:

> Florian Weimer <fw(at)deneb(dot)enyo(dot)de> writes:
>> Can I embed the types I'm interested in into my program, or should I
>> query the server at least once per connection to get the mapping? I'm
>> interested in types such as INTEGER, TEXT, BYTEA, etc. No user
>> defined types, and nothing fancy. Ultra-long-term portability isn't
>> required, either.
>
> Well, the type OIDs of the standard built-in types haven't changed in
> at least ten years, but that doesn't mean we won't change 'em in the
> future. I'd advise at least using the #define's from pg_type.h rather
> than writing actual numeric constants.

Okay, will do that. Thanks.

By the way, the binary encoding would be pretty useful for BYTEA
columns and parameters, but it's a pretty hefty burden for almost
anything else. Wouldn't it make sense to add a format flag which
basically says "binary if it's BYTEA, otherwise text"? I don't think
many host languages make a strong distinction between BYTEA and TEXT
types (except those which use UTF-16 and expose that to the user, like
Java and C#). As a result, it is difficult to specify the right types
when talking to the server. You don't want to label a column as BYTEA
overeagerly because it will break type inference on the SQL side (I
think).