[Pgpool-general] Multi-statement queries

[Daniel.Crespo at l-3com.com]

My experience is also that multi-statement queries ("statement1; statement2; ...; statementN;") work in pgpool-II, so now I'm confused with "pgpool-II cannot process multi-statement query". Also, why wouldn't it work if PostgreSQL itself does? I think the idea is pgpool-II to work transparently as connecting directly to PostgreSQL.

Daniel

> -----Original Message-----
> From: pgpool-general-bounces at pgfoundry.org [mailto:pgpool-general-
> bounces at pgfoundry.org] On Behalf Of Matthias Tief
> Sent: Tuesday, March 09, 2010 4:11 AM
> To: pgpool-general at pgfoundry.org
> Subject: Re: [Pgpool-general] Multi-statement queries
> 
> Thank you for your rapid answer.
> 
> But for me it is still not clear. What you describe seems to be a
> collection of statements transmitted as a single transaction. But this
> is done very well by pgpool-II in my tests. I am wrong with that?
> 
> So than my question is: What is the difference between "multi-statement
> queries" and a single transaction of multiple statements?
> 
> As I understand pgadmin implicitly wrapps a BEGIN/COMMIT block around
> all statements, that it becomes a single transaction.
> 
> Looking forward to your answer.
> 
> Matthias
> 
> Guillaume Lelarge schrieb:
> > Le 05/03/2010 09:45, Matthias Tief a écrit :
> >> Hallo,
> >>
> >> we are planning to use pgpool-II as replication solution for our
> >> PostgeSQL application. Currently we evaluate, whether the
> restriction of
> >> pgpool-II affect our application. In the documentation you say:
> >> "pgpool-II cannot process multi-statement query." What do you
> exactly
> >> mean with "multi-statement queries". As I found out you don't mean
> >> transactions that contain multiple statments, like BEGIN - COMMIT
> >> blocks. These blocks are "committed" or in case of a failure are
> "rolled
> >> back" correctly. I would appreciate if you could give me an example
> of
> >> multi-statement queries.
> >>
> >
> > "statement1; statement2; statement3;" in a single trip to the
> backend.
> >
> > For example:
> >
> > "INSERT INTO t1 VALUES (1); INSERT INTO t1 VALUES (2); INSERT INTO t1
> > VALUES (3);"
> >
> > is a multi-statement query, whereas
> >
> > "INSERT INTO t1 VALUES (1);"
> > then
> > "INSERT INTO t1 VALUES (2);"
> > then
> > "INSERT INTO t1 VALUES (3);"
> >
> > are three one-statement queries.
> >
> > pgAdmin uses this quite a lot ("SET client_encoding TO utf8; SELECT *
> > FROM...").
> >
> >
> 
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