Re: FW: PreparedStatement#setString on non-string parameters

Hello Antony,

I honestly don't know. Oliver Jowett told me that the 8.0 driver is the
first to use server side prepared statements, which is good I guess. I do
not know the internals of PostgreSQL server statement caching but usually
using server side prepared statements is faster than emulating prepared
statements in the JDBC driver. In cases where statements are really
exectuted once only and the PreparedStatement is used for parameter
substitution convenience only (which is a very good reason, BTW) emulated
statements are usually faster.

I just tested with the 7.4 driver and that actually works fine. It also
fixed the setString error I got when using the James mail server with the
8.0 driver...

I can not say anything about performance in comparison to the 8.0 driver
yet. Oliver mentioned poor blob-performance in the pre-8 protocol. I am not
very happy with that since we use blobs quite frequently, be it that they
are are never very large.

I will be doing some tests with the 8.0 driver in combination with a
implicit cast versus the 7.4 driver. I will keep you posted...

Regards,

Silvio Bierman



@-----Original Message-----
@From: pgsql-jdbc-owner@postgresql.org
@[mailto:pgsql-jdbc-owner@postgresql.org]On Behalf Of Antony Paul
@Sent: Wednesday, March 09, 2005 4:59 AM
@To: Oliver Jowett
@Cc: Silvio Bierman; PostgreSQL JDBC
@Subject: Re: FW: [JDBC] PreparedStatement#setString on non-string
@parameters
@
@
@Does this new stuff added in 8.0 driver adds to performance ?. I had
@this setString() problem and I tested 7.4.x driver which works and
@performs better than 8.0 driver.
@
@
@
@On Wed, 09 Mar 2005 10:47:34 +1300, Oliver Jowett
@<oliver@opencloud.com> wrote:
@> Silvio Bierman wrote:
@>
@> > Either the JDBC drivers for the databases I mentioned earlier do the
@> > conversion or the database backends do it on the server side.
@Any way, this
@> > works in all cases. PostgreSQL is the first database to break our
@> > application due to this behaviour. We have had problems on
@earlier versions
@> > of MySQL because of lack of subselect support etc. but never
@these issues.
@>
@> I'd suggest using CAST in your SQL -- that in theory should work
@> everywhere and reflects your application's intent (to interpret a string
@> as a numeric value).
@>
@> The problem with reverting to the old way of doing parameters (direct
@> text substitution into the query) is that we cannot take advantage of
@> most of the new stuff in the V3 protocol -- that means no server-side
@> prepared statement reuse, no low-overhead transfer of large parameters,
@> and reduced support for cursor-based resultsets.
@>
@> -O
@>
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@
@
@--
@rgds
@Antony Paul
@http://www.geocities.com/antonypaul24/
@
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