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Re: Using GROUP By or @OrderColumn in JPA

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From	Cecil Westerhof <Cecil@decebal.nl>
Newsgroups	comp.lang.java.programmer
Subject	Re: Using GROUP By or @OrderColumn in JPA
Date	Thu, 26 Nov 2015 07:28:20 +0100
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On Thursday 26 Nov 2015 02:02 CET, Arne Vajhøj wrote:

> On 11/25/2015 3:07 AM, Cecil Westerhof wrote:
>> 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?
>
> How did you do it before with SQL?

This was never done with SQL. They made a JPQL query that was badly
written. I managed to help rewrite it, so it is a bit clearer what is
happening. But everything was done over instant message, which is not
ideal. Today we will meet face to face and I hope to get a better
understanding of what they want and have.

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

Thread

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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