Hi Ivan, thank you for the patch.
> On 22 Nov 2023, at 03:58, Ivan Trofimov <i.trofi...@yandex.ru> wrote: > > Currently libpq sends B(ind), D(escribe), E(execute), S(ync) when executing a > prepared statement. > The response for that D message is a RowDescription, which doesn't change > during prepared > statement lifetime (with the attributes format being an exception, as they > aren't know before execution) . From my POV the idea seems reasonable (though I’m not a real libpq expert). BTW some drivers also send Describe even before Bind. This creates some fuss for routing connection poolers. > In a presumably very common case of repeatedly executing the same statement, > this leads to > both client and server parsing/sending exactly the same RowDescritpion data > over and over again. > Instead, library user could acquire a statement result RowDescription once > (via PQdescribePrepared), > and reuse it in subsequent calls to PQexecPrepared and/or its async friends. But what if query result structure changes? Will we detect this error gracefully and return correct error? Best regards, Andrey Borodin.
