Re: Entities created in one query not available in another in extended protocol

On 11 June 2015 at 22:12, Shay Rojansky <roji(at)roji(dot)org> wrote:

> Thanks everyone for your time (or rather sorry for having wasted it).
>
> Just in case it's interesting to you... The reason we implemented things
> this way is in order to avoid a deadlock situation - if we send two queries
> as P1/D1/B1/E1/P2/D2/B2/E2, and the first query has a large resultset,
> PostgreSQL may block writing the resultset, since Npgsql isn't reading it
> at that point. Npgsql on its part may get stuck writing the second query
> (if it's big enough) since PostgreSQL isn't reading on its end (thanks to
> Emil Lenngren for pointing this out originally).
>

That part does sound like a problem that we have no good answer to. Sounds
worth starting a new thread on that.

> Of course this isn't an excuse for anything, we're looking into ways of
> solving this problem differently in our driver implementation.
>
> Shay
>
> On Thu, Jun 11, 2015 at 6:17 PM, Simon Riggs <simon(at)2ndquadrant(dot)com>
> wrote:
>
>> On 11 June 2015 at 16:56, Shay Rojansky <roji(at)roji(dot)org> wrote:
>>
>> Npgsql (currently) sends Parse for the second command before sending
>>> Execute for the first one.
>>>
>>
>> Look no further than that.
>>
>>

--
Simon Riggs http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services