Groups > comp.lang.java.programmer > #33197

Using GROUP By or @OrderColumn in JPA

From	Cecil Westerhof <Cecil@decebal.nl>
Newsgroups	comp.lang.java.programmer
Subject	Using GROUP By or @OrderColumn in JPA
Date	2015-11-25 09:07 +0100
Organization	Decebal Computing
Message-ID	<87bnai8pu7.fsf@Equus.decebal.nl> (permalink)

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We are working on our first project with JPA. We had some bumps in the
road, but I find it a good tool.

We have an entity request which has a one to many relationship with
estimate which has a one to one relationship with decision. One of the
fields of decision is date.

We need request-estimate-decision's where the date field of decision
is not null and has the highest value. (We are only interested in the
latest decision pro request.)

I was thinking about a GROUP BY, but someone else thought about
@OrderColumn. But if I understand it correctly an @OrderColumn needs
an Integer and an index. We cannot change the database definition. So
I suppose that @OrderColumn is not an option and we need to use the
GROUP BY?

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

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Using GROUP By or @OrderColumn in JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-25 09:07 +0100
  Re: Using GROUP By or @OrderColumn in JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-25 20:02 -0500
    Re: Using GROUP By or @OrderColumn in JPA Cecil Westerhof <Cecil@decebal.nl> - 2015-11-26 07:28 +0100
      Re: Using GROUP By or @OrderColumn in JPA Jerry Stuckle <jstucklex@attglobal.net> - 2015-11-26 08:25 -0500
      Re: Using GROUP By or @OrderColumn in JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-26 20:22 -0500
        Re: Using GROUP By or @OrderColumn in JPA Silvio <silvio@internet.com> - 2015-11-27 12:28 +0100
          Re: Using GROUP By or @OrderColumn in JPA Jerry Stuckle <jstucklex@attglobal.net> - 2015-11-27 09:22 -0500
            Re: Using GROUP By or @OrderColumn in JPA Silvio <silvio@internet.com> - 2015-11-27 17:42 +0100
              Re: Using GROUP By or @OrderColumn in JPA Silvio <silvio@internet.com> - 2015-11-27 17:43 +0100
                Re: Using GROUP By or @OrderColumn in JPA Martin Gregorie <martin@address-in-sig.invalid> - 2015-11-27 18:21 +0000
          Re: Using GROUP By or @OrderColumn in JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-28 23:01 -0500
            Re: Using GROUP By or @OrderColumn in JPA Silvio <silvio@internet.com> - 2015-11-29 12:42 +0100
        Re: Using GROUP By or @OrderColumn in JPA Arne Vajhøj <arne@vajhoej.dk> - 2015-11-28 22:44 -0500
      Re: Using GROUP By or @OrderColumn in JPA Martin Gregorie <martin@address-in-sig.invalid> - 2015-11-27 11:07 +0000

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