Re: BUG #2695: Randomly repeated query execution

On Mon, 16 Oct 2006, Jakub wrote:
>
> The following bug has been logged online:
>
> Bug reference:      2695
> Logged by:          Jakub
> Email address:      kuna44@wp.pl
> PostgreSQL version: Postgres 7.4
> Operating system:   Linux
> Description:        Randomly repeated  query execution
> Details:
>
> Sometimes, randomly single query execution is repeated   twice or more in
> 2-5 second.
>
> Thanks,
> Jakub
>

Jakub,

I've seen this type of thing before, but it wasn't Postgres' fault. In the
examples I've seen (on many different occasions, in differing
circumstances) the application was actually issuing the query multiple
times and usually the cause of that was improper (multiple) event handling
by the application's GUI. In particular, if the language is Java, look for
errant event-handling methods.

I've also seen this type of error caused by error handling packages that
attempt to auto-recover based on various errors when they have a bug
regarding what kinds of errors are recoverable and which are not. As
examples, a lost network link may be recoverable, but an attribute not
existing in a table/relation is not.

Try some very careful coding around the suspect queries to log in your own
code whether queries are being repeated or not.

Regards,
Richard


-- 
Richard Troy, Chief Scientist
Science Tools Corporation
510-924-1363 or 202-747-1263
rtroy@ScienceTools.com, http://ScienceTools.com/