Mauro,
If it's just a count, another option would be to just use a
@NamedNativeQuery(name="SELECT count(*) FROM Tabelat") instead of using
JPQL. If this is an option, this might be a lot simpler/easier than
extending a class.

regards,
Judes Tumuhairwe



On Thu, Dec 17, 2009 at 2:48 PM, Miłosz Tylenda <[email protected]> wrote:

> Hi Mario,
>
> You are right. The processing of your JPQL query does not go through the
> method I suggested. Instead, it is handled in classes from the
> org.apache.openjpa.jdbc.kernel.exps package - mainly Count class and
> UnaryOp.appendTo method. You could probably modify the appendTo method to
> suit your need. However, I guess you don't want to modify the OpenJPA source
> code but provide some extension only. This might be impossible for these
> classes, at least I don't know the way to do it.
>
> My other idea then is to look at getSelects and toSelect methods in
> DBDictionary.
>
> Hope this helps,
> Milosz
>
>
> >
> >
> > I  had tried it already, Milosz.
> > But this overwritten method doesn't seem to be running. I debugged it,
> > others overwritten methods runs.
> >
> >
> >
> > Miłosz Tylenda wrote:
> > >
> > > Mauro,
> > >
> > > I would start with looking at DBDictionary.toSelectCount method.
> > >
> > > Regards,
> > > Milosz
> > >
> > >
> > >> The  jpql:  "SELECT count(o) FROM Object o" (A)
> > >>
> > >> is usually translated to this sql: "SELECT count(t.primarykey) FROM
> Table
> > >> t"
> > >> (B)
> > >>
> > >> I'm working with a legacy database witch jdbc driver doesn't accept
> this
> > >> format of sql.
> > >> It works with: "SELECT count(*) FROM Tabelat" (C)
> > >>
> > >> Is there a way to make the query C (with count(*)) be generated
> instead
> > >> of
> > >> query B?
> > >>
> > >> I'm using the default jpa dictionary.  I know that I can extend
> > >> DBDictionary
> > >> in order to customize this.
> > >> I had some difficulty trying to do this.
> > >>
> > >> Somebody would give some hint?
> > >>
> > >> Thanks. Mauro.
> > >>
> > >> --
> > >> View this message in context:
> > >> http://n2.nabble.com/COUNT-t-to-COUNT-tp4176827p4176827.html
> > >> Sent from the OpenJPA Users mailing list archive at Nabble.com.
> > >
> > >
> > >
> >
> > --
> > View this message in context:
> http://n2.nabble.com/COUNT-t-to-COUNT-tp4176827p4182603.html
> > Sent from the OpenJPA Users mailing list archive at Nabble.com.
> >
>

Reply via email to