Btw., this also allows doing things like
SELECT $1, $2
\bind '1' '2' \g
\bind '3' '4' \g
That's one of the things I was hoping for. Very cool.
This isn't a prepared statement being reused, but it relies on the fact
that psql \g with an empty query buffer resends the previous query.
Still kind of neat.
Yeah, if they wanted a prepared statement there's nothing stopping them.
Review:
Patch applies, tests pass.
Code is quite straightforward.
As for the docs, they're very clear and probably sufficient as-is, but I wonder if we should we explicitly state that the bind-state and bind parameters do not "stay around" after the query is executed? Suggestions in bold:
This command causes the extended query protocol (see <xref
linkend="protocol-query-concepts"/>) to be used, unlike normal
<application>psql</application> operation, which uses the simple
query protocol.
Extended query protocol will be used even if no parameters are specified, so this command can be useful to test the extended
query protocol from psql. This command affects only the next query executed, all subsequent queries will use the regular query protocol by default.
Tests seem comprehensive. I went looking for the TAP test that this would have replaced, but found none, and it seems the only test where we exercise PQsendQueryParams is libpq_pipeline.c, so these tests are a welcome addition.
Aside from the possible doc change, it looks ready to go.
