Re: [GENERAL] 7.3 Prepared statements [Viruschecked]

Patric Bechtel <bechtel@ipcon.de>

From: "Patric Bechtel" <bechtel@ipcon.de>
To: "pgsql-jdbc@postgresql.org" <pgsql-jdbc@postgresql.org>
Date: 2003-01-03T09:35:16Z
Lists: pgsql-general
On Thu, 2 Jan 2003 23:47:05 -0500 (EST), Bruce Momjian wrote:

>
>I would ask on the jdbc lists.  I am Cc'ing them, and removing the
>general list.
>
>---------------------------------------------------------------------------
>
>Charles H. Woloszynski wrote:
>> Bruce:
>> 
>> Do you mean that, under JDBC with PG7.3, it will use the stored 
>> execution plan, or that we should ask the JDBC driver maintainers to 
>> work to use this feature to use the stored executiong plan?
>> 
>> I am obviously interested in helping make this happen to improve the 
>> overall PostgreSQL solution.  Should I contact someone specific about 
>> this to see if there are plans to make this happen in the near future? 
>>  I think I have a solid framework to test its effectiveness with decent 
>> performance monitoring tools already in place.
>> 
>> Thanks,
>> 
>> Charlie


As I dipped my nose a bit deeper into that the last few days, I think
I can tell you that the JDBC driver (7.3.1 and the current CVS)
doesn't use server side prepared statements automatically.
I changed that with a patch I announced yesterday. As soon as it will
be accepted, it will.
If you want to try it out *NOW*, you should to something like this:
((org.postgresql.jdbc1.AbstractJdbc1Statement)statement).setUseServerPrepare(true);
It's kind of clumsy, and does clue your app to pgsql a bit, but for
a test, it's ok. 
(You could also try out my patch, it's on the pgsql-patches list :-))
Don't overestimate the performance win for prepared statements, as the
optimizer can NOT really calculated the perfect plan, if the statement
is too unspecific.
At the moment there's a bug regarding boolean values in server side
prepared statements. My patch fixes this, too. I hope it will be
applied soon...

tia

Patric