Re: [HACKERS] Revised proposal for libpq and FE/BE protocol changes

>
> Tom Lane wrote:
> >
> > Here is a revised proposal that takes into account the discussions
> > of the last few days.  Any comments?
>
> Just one at the end
>
> [snip]
>
> > 4. The frontend may request cancellation of the current query by sending
> > a single byte of OOB (out-of-band) data.  The contents of the data byte
> > are irrelevant, since the cancellation will be triggered by the associated
> > signal and not by the data itself.  (But we should probably specify that
> > the byte be zero, in case we later think of a reason to have different
> > kinds of OOB messages.)  There is no specific reply to this message.
> > If the backend does cancel a query, the query terminates with an ordinary
> > error message indicating that the query was cancelled.
>
> You didn't come right out and say it, but are you intending to support
> multiple queries within a connection?  I gather not.  Not that I'm
> suggesting that this be done, as it seems this would complicate the
> user's application and the backend.  With only one possible OOB
> message, you can't tell it which query to cancel.
>
> Ocie Mitchell

Waves hand wildly... I know, I know!

   All of them!

-dg

David Gould            dg@illustra.com           510.628.3783 or 510.305.9468
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