Re: [PERFORM] join over 12 tables takes 3 secs to plan

I have been asking (and learning) about this same thing on the 
PGSQL-JDBC mailing list.  Apparently, there is a new driver for 7.3 that 
can store the plan on the server (aka, preparing it on the server) and 
re-use it.  However, you need to set the PreparedStatement to do this 
for each statement.  So, yes, you can retain the plan but it looks like 
you need to do some work to make it stick.  [Also, you need to retain 
the PreparedStatement, it is not cached based based on the text of the
statement, but associated with the PreparedStatement itself].

I think the functionality is starting to become real, but it looks like 
it is starting with some limitations that might restricts its use from 
be maximally realized until 7.4 (or beyond).

Charlie




Hilmar Lapp wrote:

>
> On Friday, January 3, 2003, at 09:12  AM, Jeff wrote:
>
>> Hmm.. This won't fix the fact the planner takes three seconds, but since
>> it is a web application have you tried using PREPARE/EXECUTE so it only
>> needs to be planned once?
>
>
> Interesting point. I'd have to look into the source code whether the 
> guy who wrote it actually uses JDBC PreparedStatements. I understand 
> that PostgreSQL from 7.3 onwards supports prepared statements (cool!). 
> Would the JDBC driver accompanying the dist. exploit that feature for 
> its PreparedStatement implementation?
>
>     -hilmar


-- 


Charles H. Woloszynski

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