Re: single click, double query

On Thu, 15 Dec 2005, Szabolcs BALLA wrote:

> Hi,
>
> I have a strange problem with psql 7.4.7.
> I have customers who run xp, with sp1 (with sp2 no problem), when they
> report from our web-based application they send a query
> after a single click. The same queries have been posted twice within a
> few milliseconds.
> How can I forbid this on db server side? Is it possible?

Not easily that I can think of. Something between the two that passes
connections but filters queries might be reasonably easy to make. I see
two possible problems with this on the server side though. First, if
those are coming in separate connections then you have to either delay for
the first query or pay the cost of making a database backend even if
you're going to drop it if its a duplicate. Second, if it's possible for
two client instances to send the same query then you could break the
application in the other direction where the second client gets no
response.