Re: batching commands with libpq

hi,

> yamt(at)mwd(dot)biglobe(dot)ne(dot)jp (YAMAMOTO Takashi) writes:
>> is there any way to send multiple commands together (ideally in a single
>> network packet), and then wait for their results, using libpq? i want to
>> save extra round-trips. while postgresql's fe-be on-wire protocol seems
>> to allow it (is it right?), i couldn't find a way with libpq.
>
>> PQsendQuery(conn, "select timeofday();select timeofday();select timeofday();");
>> seems to work, but i want to use extended protocol.
>
> You're out of luck: extended protocol intentionally doesn't allow
> multiple queries per string.
>
> The wire protocol does in theory allow you to send more commands before
> waiting for the results of the first one, but that's not supported in
> libpq. The only case you can do in libpq is multiple commands in a
> PQexec string.

thanks for explanation.
do you think it's worth extending the libpq api to allow two or
more in-flight commands?

YAMAMOTO Takashi

>
> regards, tom lane