Message-ID: <b92c6822df72932379da29ded319391b81cb2cf8.camel@cybertec.at>
Subject: Re: libpq simple SELECT
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Igor Korot <ikorot01@gmail.com>, "pgsql-generallists.postgresql.org"
	 <pgsql-general@lists.postgresql.org>
Date: Wed, 17 Dec 2025 08:34:51 +0100
In-Reply-To: <CA+FnnTzP_9Mh9S7NJL5WFJmbOi2wxw4g=MdoUo-SuXEp3Fyg-g@mail.gmail.com>
References: 
	<CA+FnnTzP_9Mh9S7NJL5WFJmbOi2wxw4g=MdoUo-SuXEp3Fyg-g@mail.gmail.com>
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On Tue, 2025-12-16 at 21:49 -0800, Igor Korot wrote:
> I just tried the following code:
>=20
> [code]
>     std::wstring query1 =3D L"SELECT t.table_catalog AS catalog,
> t.table_schema AS schema, t.table_name AS table, u.usename AS owner,
> c.oid AS table_id FROM information_schema.tables t,
> pg_catalog.pg_class c, pg_catalog.pg_user u WHERE t.table_name =3D
> c.relname AND c.relowner =3D usesysid AND (t.table_type =3D 'BASE TABLE'
> OR t.table_type =3D 'VIEW' OR t.table_type =3D 'LOCAL TEMPORARY') ORDER B=
Y
> table_name;";
>         res =3D PQexec( m_db, m_pimpl->m_myconv.to_bytes( query1.c_str()
> ).c_str() );
>          for( int i =3D 0; i < PQntuples( res ); i++ )
>          {
> some code handling the results
>          }
> [/code]
>=20
> The loop is executed exactly 1 time.
>=20
> My question is - according to the comment above I don't have to use curso=
r,
> but it looks like it's unavoidable?

I see no cursor in your example...

Yours,
Laurenz Albe