Date: Thu, 01 Apr 2021 15:30:05 +0000
To: Tom Lane <tgl@sss.pgh.pa.us>
From: Giovani Garcia <giovani.garcia@protonmail.com>
Cc: "pgsql-interfaces@lists.postgresql.org"
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Reply-To: Giovani Garcia <giovani.garcia@protonmail.com>
Subject: Re: Doubt regarding query parameter metadata
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Hello Tom,

Thanks for taking the time.

> Is that theexact query you're issuing?
Yes, that's the exact query.
You can reproduce the issue by creating the table and running the C program=
 from my previous e-mail.


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On Thursday, 1 April 2021 11:14, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> Giovani Garcia giovani.garcia@protonmail.com writes:
>
> > The issue I'm finding is that the Oid returned for a VARCHAR column is =
TEXTOID (25) instead of VARCHAROID (1043).
>
> This isn't hugely surprising in general. varchar has no operations
> of its own; PG treats it as sort of a domain over text. So if you
> do anything at all to a varchar column, it'd be quite likely for
> the column to be implicitly coerced to text within the query.
>
> > Now, when I run the following program (simplified for brevity),
>
> > "SELECT key FROM oid_test WHERE value =3D $1",
>
> Is that theexact query you're issuing? I don't see anything
> in that that would cause a coercion, but maybe you left out some
> relevant detail.
>
> regards, tom lane