Pipelining INSERTs using libpq

I would like to pipeline INSERT statements. The idea is to avoid
waiting for server round trips if the INSERT has no RETURNING clause and
runs in a transaction. In my case, the failure of an individual INSERT
is not particularly interesting (it's a "can't happen" scenario, more or
less). I believe this is how the X toolkit avoided network latency issues.

I wonder what's the best way to pipeline requests to the server using
the libpq API. Historically, I have used COPY FROM STDIN instead, but
that requires (double) encoding and some client-side buffering plus
heuristics if multiple tables are filled.

It does not seem possible to use the asynchronous APIs for this purpose,
or am I missing something?

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Florian Weimer / Red Hat Product Security Team