Re: Async PQgetResult() question.

Uh oops! I misread IIRC as (IRC, i.e. Internet Relay Chat or something
similar.) It is too early! ;) I'll dig in the archives.

Thanks,
Matthew

At 12:03 PM 7/8/2001 -0400, Matthew Hagerty wrote:
>At 11:44 PM 7/7/2001 -0400, Tom Lane wrote:
>>Matthew Hagerty <mhagerty(at)voyager(dot)net> writes:
>> > So then how would I code for the exception, i.e. the backend goes down
>> just
>> > before or during my call to PQsendQuery()? If I am non-blocking then
>> I can
>> > determine that my query did not go (PQsendQuery() or PQflush() returns an
>> > error) and attempt to recover.
>>
>>This is the nasty part of any async client, all right. The case of a
>>backend crash doesn't bother me particularly: in the first place, you'll
>>get back a "connection closed" failure quickly, and in the second place,
>>backend crashes while absorbing query text (as opposed to while
>>executing a query) are just about unheard of. However, the possibility
>>of loss of network connectivity is much more dire: it's plausible, and
>>in most cases you're looking at a very long timeout before the kernel
>>will decide that the connection is toast and report an error to you.
>>
>>I'm unconvinced, however, that using PQsetnonblocking improves the
>>picture very much. Unless the database operations are completely
>>noncritical to what your app is doing, you're going to be pretty
>>much dead in the water anyway with a lost connection :-(
>>
>>In the end you pays your money and you takes your choice. I do
>>recommend reading my past rants about why PQsetnonblocking is broken
>>(circa Jan 2000, IIRC) before you put any faith in it. If you end
>>up deciding that it really is something you gotta have, maybe you'll
>>be the one to do the legwork to make it reliable.
>>
>> regards, tom lane
>
>
>Well, I guess sending a query will have to be my weak link for the moment,
>heck, that's why we have version releases, right? ;) I'll take your
>advise and disable PQsetnonblocking for now, but I would like to read your
>rants and maybe (if I think I can muster the courage), look into fixing
>PQsetnonblocking. I have never dug around for an IIRC archive before,
>might you recommend one that contains your rants?
>
>Thanks,
>Matthew
>
>
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