On Tue, Mar 4, 2025 at 1:57 AM Michael Paquier <michael@paquier.xyz> wrote:
> Anyway, can we really say that the set of printQueryOpt saved at
> execution is the correct set to use? It is possible to have the
> opposite argument and say that we should just apply the printQueryOpt
> at the moment where \getresult is run. A benefit of that it to keep
> the loop retrieving results simpler in ExecQueryAndProcessResults(),
> because we pass down to this call *one* printQueryOpt as "opt".
>
> There's of course the simplicity argument that I do like a lot here,
> but applying the printing options at the time of \getresult feels also
> more natural to me.
Saving the printQueryOpt when a command is pushed was an option I had
in mind if that was straightforward to implement. However, even with
savePsetInfo, you will need to save values like gfname and gset_prefix
since it impacts the output (it may make sense to move those in
printQueryOpt). This would also need to be saved for all commands,
like \close or \parse since we don't distinguish if a piped command
generates an output or not. So that definitely looks like it would add
a lot of complexity for limited benefit.
> FWIW, I agree that HEAD is unbalanced with its handling of \gx, so we
> could do one of the following two things:
> 1) Ignore any formatting options given to \g, but also allow \gx to
> run, documenting that during a pipeline the formatting options are
> ignored, and that the set of options defined when doing a \getresult
> is the only thing that matters.
> 2) Invent a new meta-command (suggested by Daniel Verite off-list, and
> not published to the lists because I don't know how to do a
> reply-all), like a \send, a \push, forbiding entirely \gx and \g when
> in a pipeline. If we were to integrate options into this new
> meta-command, a split with \g would make an integration easier to
> think about. One name suggestion I can come up is \sendpipeline.
>
> I'd consider option 2, based on Daniel's concerns. One line I'm going
> to draw here is that we should not go down to manipulations of
> printQueryOpt while retrieving batch of results depending on the style
> of output that was defined when sending a query in a pipeline.
Another possible option would be to directly send the command without
requiring an additional meta-command, like "SELECT 1 \bind". However,
this would make it more painful to introduce new parameters, plus it
makes the \bind and \bind_named inconsistent as it is normally
required to send the result with a separate meta-command.
I like the \sendpipeline option. It makes it clearer that formatting
options are not applicable within a pipeline (at least, in the current
implementation) and I think it would make more sense to have those
formatting options in \getresults or \endpipeline.
I took a stab at creating the \sendpipeline meta-command. I've also
realised there's a small leak where fname is currently not freed on
queries like 'select ... \bind \gx filename' when within a pipeline,
which is fixed in patch 0001.
