Re: Extend libpq to support mixed text and binary results

On Wed, Nov 7, 2012 at 7:08 AM, Albe Laurenz <laurenz(dot)albe(at)wien(dot)gv(dot)at> wrote:
> The Frontend/Backend protocol's "bind" message allows to
> specify mixed text and binary result formats, but there
> is not support in the C API for that.
>
> I'd like to add support for that to libpq for these reasons:
>
> - I think that every feature of the line protocol should
> be exposed in the C API.
>
> - This is quite useful if you select bytea and other
> fields in one query (less overhead and data traffic
> for the bytea).
>
> - I've seen at least one case on the list where
> somebody would have liked to have that feature:
> http://archives.postgresql.org/pgsql-general/2012-08/msg00761.php
>
> Attached is a WIP patch that adds four new functions
> to libpq:
> PQexecParams2
> PQexecPrepared2
> PQsendQueryParams2
> PQsendQueryPrepared2
>
> If that idea meets with approval, I'd add documentation and
> submit it to the next commitfest.
>
> I am aware that these names are rather ugly and welcome
> better ideas.
>
> Maybe it is not necessary to add four new functions.
> You could get the full functionality just with
> PQsendQueryPrepared2, the rest is just for ease of use.

How would this compare to libpqtypes which I might in-humbly suggest
is the gold standard in terms of dealing with libpq binary formats: it
pulls everything in binary and puts the complicated stuff in structs
so you don't have to parse.

merlin