Re: libpq, PQdescribePrepared -> PQftype, PQfmod, no PQnullable - Mailing list pgsql-hackers

From Florian Pflug
Subject Re: libpq, PQdescribePrepared -> PQftype, PQfmod, no PQnullable
Date
Msg-id A765937A-1F41-47DB-B606-93E2FB2E8C38@phlo.org
Whole thread Raw
In response to Re: libpq, PQdescribePrepared -> PQftype, PQfmod, no PQnullable  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
Responses Re: libpq, PQdescribePrepared -> PQftype, PQfmod, no PQnullable
List pgsql-hackers
On Oct9, 2011, at 14:20 , Kevin Grittner wrote:
> Florian Pflug  wrote:
> 
>> Coming up with a reasonable algorithm isn't *that* hard.
> 
> Agreed.  Our shop has used a home-grown framework for over a decade
> where we parse queries using ANTLR ( http://www.antlr.org/ ) and we
> tracked this trough all expressions.  There really weren't that many
> situations where we had to punt.

Sounds cool. What was your use-case for doing that?

>> D) All others are nullable
> 
> I think you meant "All others are not nullable."

Ups, yeah, right, that was supposed to read *non*-nullable.

>> That might be a rather tough sell, as least as long as there's
>> isn't a clear use-case for this. Which, unfortunately, nobody has
>> provided so far.
> 
> Yeah.  It would be nice to see at least one use case.  The only
> comment I recall is a vague suggestion that that people might want to
> select data from a table and infer table attributes from the result
> set metadata.  That seems marginal.

Well, there is one other, namely SQL standards compliance. It does
mandate that "CREATE TABLE ... AS SELECT" creates NOT NULL constraints
on non-nullable columns I think (I didn't re-check, though). I'm not sure
I see the value in that either, but, hey, standards compliance ought
to be a value it in itself, right?

>> the question is simply whether one values to feature enough to put
>> in the word.
> 
> ... or fund the work.  There are people for hire in the community.

And that was, of course, supposed to read "put in the *work*". Alas, just
putting in the *word* is probably not going to be enough ;-)

best regards,
Florian Pflug



pgsql-hackers by date:

Previous
From: "Kevin Grittner"
Date:
Subject: Re: libpq, PQdescribePrepared -> PQftype, PQfmod, no PQnullable
Next
From: Florian Pflug
Date:
Subject: Re: WIP: Join push-down for foreign tables