Re: BUG #5720: Bug for PQescapeByteaConn (libpq)

On Saturday 23 October 2010 06:46:31 Craig Ringer wrote:
> On 23/10/2010 1:11 AM, Tom Lane wrote:
> > "Eiichi Nakamura"<nakamura(at)nepsys(dot)ddo(dot)jp> writes:
> >> For PostgreSQL 9.0.1, after changing server "bytea_output" parameter as
> >> "escape" in postgresql.conf file, it is expected that PQescapeByteaConn
> >> (libpq) returns "escape" format.
> >
> > Why do you expect that? The parameter only controls the *server*'s
> > output, it is not suggested anywhere that it should have an effect
> > on clients.
>
> IMO it seems like a reasonable expectation on the face of it. The client
> can tell what bytea format the server wants, as it has a connection to
> the server and the ability to read the appropriate GUC. The whole point
> of the 'Conn' functions is that they're capable of being sensitive to
> the configuration of the current connection.
The GUC controlls the output - it doesnt control the allowed input. The switch
on the client needs to get based on the version - which hopefully doesnt
change in a single connection ;-)

Andres