Обсуждение: single click, double query
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? note: I can't forbid a "too fast" connections by IP because they come throught firewall. Thanks, Szabek
On 12/15/05, Szabolcs BALLA <szballa@confinsystems.com> 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? if you see the problem just in clients with xp sp1 and not with xp sp2 then the problem is in the client not in the server... upgrade your xp clients to sp2... > note: I can't forbid a "too fast" connections by IP because they come > throught firewall. > > Thanks, > Szabek > > -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
Yes, but they are our clients, and I can't say for them: please upgrade your client because if you use our applications the db server will have a performance problem...:( Jaime Casanova wrote: >On 12/15/05, Szabolcs BALLA <szballa@confinsystems.com> 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? >> >> > >if you see the problem just in clients with xp sp1 and not with xp sp2 >then the problem is in the client not in the server... > >upgrade your xp clients to sp2... > > > >>note: I can't forbid a "too fast" connections by IP because they come >>throught firewall. >> >>Thanks, >>Szabek >> >> >> >> > > >-- >regards, >Jaime Casanova >(DBA: DataBase Aniquilator ;) > >---------------------------(end of broadcast)--------------------------- >TIP 1: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly > > >
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.