Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.java.programmer > #32996

Re: Performance JPA

Path csiph.com!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail
From Cecil Westerhof <Cecil@decebal.nl>
Newsgroups comp.lang.java.programmer
Subject Re: Performance JPA
Date Wed, 04 Nov 2015 09:48:12 +0100
Organization Decebal Computing
Lines 34
Message-ID <87egg6i20j.fsf@Equus.decebal.nl> (permalink)
References <87lhagkcsh.fsf@Equus.decebal.nl> <563763d9$0$23727$e4fe514c@news.xs4all.nl> <87d1vrk20x.fsf@Equus.decebal.nl> <56389a9e$0$23778$e4fe514c@news.xs4all.nl> <n1bnte$2j8$2@speranza.aioe.org>
Mime-Version 1.0
Content-Type text/plain; charset=utf-8
Content-Transfer-Encoding 8bit
Injection-Info mx02.eternal-september.org; posting-host="528adfd6ad074c92fdc6a7f8fb9e23d8"; logging-data="28859"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18go2bH8UufeGmWSUafK0TsFDL7GVZTJlQ="
User-Agent Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux)
Cancel-Lock sha1:jBfmADwFlpdRek5xkM/ImNz9WjA= sha1:ibdrX8HtB0n27JFtum9WH30sCvU=
X-Homepage http://www.decebal.nl/
Xref csiph.com comp.lang.java.programmer:32996

Show key headers only | View raw

On Wednesday  4 Nov 2015 02:44 CET, Arne Vajhøj wrote:

> On 11/3/2015 6:29 AM, Silvio wrote:
>> On 11/03/2015 07:52 AM, Cecil Westerhof wrote:
>>> As I understood it until now, there should be a little overhead,
>>> but it can be worse I understand now. As said in the above
>>> rowmapper was used. Now the application uses em.find to read. For
>>> displaying a page only reads are done, so using em.find instead
>>> rs.get... seems to make a very big difference. Is there a reason
>>> for this and can there be something done about this?
>
>> If you look at the executed SQL you will probably see a huge amount
>> of lookup-by-pk statements executed where in the past these where
>> relatively rare since they where mostly multi-row selects (usually
>> foreign key conditions possibly combined with other filters).
>>
>> This is typical for an application that has undergone a naive (in
>> the one-to-one sense) port to an ORM layer.
>
> Really??
>
> I have never seen such a problem.
>
> em.createQuery is easy and generate an equivalent SQL to the one
> to chose if manually written.

For read, create, update and delete we use find, persist, merge and
remove. For the other queries mostly createQuery is used. On a few
places criteria is used.

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

Back to comp.lang.java.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-02 09:47 +0100
  Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-02 14:23 +0100
    Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-03 07:52 +0100
      Re: Performance JPA Martin Gregorie <martin@address-in-sig.invalid> - 2015-11-03 11:16 +0000
        Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-03 19:11 +0100
          Re: Performance JPA Martin Gregorie <martin@address-in-sig.invalid> - 2015-11-03 19:15 +0000
            Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-04 09:28 +0100
              Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-10 08:07 +0100
                Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-10 10:35 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-11 06:20 +0100
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-11 09:32 -0500
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-10 19:56 -0500
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-11 06:50 +0100
                Re: Performance JPA Martin Gregorie <martin@address-in-sig.invalid> - 2015-11-11 12:17 +0000
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-11 09:30 -0500
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-11 23:20 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-11 23:11 +0100
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-11 19:10 -0500
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-12 07:27 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-13 08:30 +0100
                Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-13 10:45 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-13 11:06 +0100
                Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-13 13:36 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-20 09:04 +0100
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-13 21:46 -0500
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-20 09:09 +0100
          Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-03 20:35 -0500
            Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-04 09:35 +0100
              Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-07 22:09 -0500
      Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-03 12:29 +0100
        Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-03 19:23 +0100
        Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-03 20:44 -0500
          Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-04 09:48 +0100
          Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-04 10:23 +0100
            Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-04 11:27 +0100
              Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-04 12:42 +0100
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-07 22:18 -0500
                Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-09 10:43 +0100
                Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-20 09:13 +0100
            Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-07 22:12 -0500
              Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-09 10:22 +0100
                Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-10 21:35 -0500
                Re: Performance JPA Silvio <silvio@internet.com> - 2015-11-11 11:29 +0100
      Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-03 20:42 -0500
        Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-04 11:19 +0100
          Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-07 22:05 -0500
  Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-02 20:08 -0500
    Re: Performance JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-03 07:55 +0100
      Re: Performance JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-03 20:45 -0500
  Re: Performance JPA Lew <lewbloch@gmail.com> - 2015-11-16 14:43 -0800

csiph-web