Re: Add Pipelining support in psql

On Tue, Mar 18, 2025 at 09:55:21AM +0100, Anthonin Bonnefoy wrote:
> I've added additional tests when piping queries with ';':
> - I've reused the same scenario with \sendpipeline: single query,
> multiple queries, flushes, syncs, using COPY...
> - Using ';' will replace the unnamed prepared statement. It's a bit
> different from expected as a simple query will delete the unnamed
> prepared statement.
> - Sending an extended query prepared with \bind using a ';' on a
> newline, though this is not specific to pipelining. The scanned
> semicolon triggers the call to SendQuery, processing the buffered
> extended query. It's a bit unusual but that's the current behaviour.

The tests could be much more organized, particularly for the "sinple"
and "multiple" and COPY cases, rather than being treated as two
different groups at different locations of psql_pipeline.sql. I've
spent some time reorganizing all that.

A second thing that was a bit itchy is the use of ";" for what's a
semicolon, and we use this term in the psql docs to refer to queries
terminated by that. The whole paragraph could be simplified a bit
more, mentioning that everything in a pipeline uses the extended
protocol, while \bind & co are more like options. The description of
PIPELINE_COMMAND_COUNT could be simpler, and the part about the
pending results can be more general now so I've removed it.

With all that set, I've applied the patch. If you have more
suggestions, please feel free to mention them.
--
Michael