Re: Function to kill backend

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > OK, you have a runaway report. You want to stop it.  Query cancel is
> > only going to stop the current query, and once you do that the next
> > query is fed in so there is no way to actually stop the report,
> > especially if the report is not being run from the same machine as the
> > server (you can't kill the report process).
> 
> > I don't think most apps reconnect on disconnect, except maybe pooled
> > connections where you don't expect your state to be stable between
> > connections.  Certainly most reports can't just reconnect and keep
> > going.
> 
> You're hypothecating a report generator that can recover from failed
> queries, but not a failed connection?  Seems a rather contrived case.
> Stupid apps are most likely gonna curl up and die on any unexpected
> error (which is what the query cancel would look like to them).  Smart
> apps may try harder to recover than you think.

I figured some reports just continue on failed queries.  Is that
accurate?  I don't know, but I know a psql script will continue, no?
Will psql return an error code on exit from cancel?  I think it does but
am not sure.

First people objected to this on security grounds, now that those were
beat down, we have use-case complaints.  Not having a way to kill
backends is like having no way to kill a process except rebooting the
server.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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