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From: Cecil Westerhof <Cecil@decebal.nl>
Newsgroups: comp.lang.java.programmer
Subject: Re: Performance JPA
Date: Thu, 12 Nov 2015 07:27:20 +0100
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On Thursday 12 Nov 2015 01:10 CET, Arne Vajhøj wrote:

> That persistence.xml does not look correct.
>
> <property name="openjpa.ConnectionDriverName"
> value="com.ibm.db2.jcc.DB2Driver" />
>
> specifies a JDBC driver not DataSource.
>
> That may (*) make JPA not use WAS connection pool but try to
> establish a connection for every operation. And that is very bad.

That was what I thought was happening. (A new connection every time.)


> The technique may work fine for a local database with a simple login
> protocol but with a remote database and complex protocol, then it
> could create a huge overhead.
>
> But we would need to see the rest of the persistence,xml to be sure
> (the standard part actually determines whether it is driver or
> data source).
>
> Try see:
>
> http://stackoverflow.com/questions/3526434/ibm-websphere-jpa-configuration-how-to-update-persistence-xml
>
> for an example of a persistence.xml that looks way
> more I would expect (no driver, data source, all managed).

I have been trying some things, but until now without success. I need
to go to the office again and from there I do not have newsgroup
access, so some silence on my part again. I will communicate my
progress when I am back home.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof