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https://issues.apache.org/jira/browse/JDO-721?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14116502#comment-14116502
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Andy Jefferson commented on JDO-721:
------------------------------------

Perhaps this should be in 3.1 if the meeting minutes asks what else could be 
done in 3.1? That depends on the timescales for 3.1 getting released.
The RI provides it. The spec update is minor. The only remaining thing is a TCK 
test - just extend an existing test and add a null value for the ordered field 
and check the placement.

> Specifying NULL elements positioning in ordered columns
> -------------------------------------------------------
>
>                 Key: JDO-721
>                 URL: https://issues.apache.org/jira/browse/JDO-721
>             Project: JDO
>          Issue Type: Improvement
>          Components: specification
>    Affects Versions: JDO 3 update 1 (3.0.1)
>            Reporter: Muhammad Gelbana
>            Priority: Minor
>              Labels: jdoql
>             Fix For: JDO 3.2
>
>
> I don't know about other RDBMS but in MySQL ordering, it's possible to 
> specify whether NULL column fields are placed in the beginning or at the end 
> of the ordering, i.e.:
> ORDER BY `values_column` IS NULL DESC
> [values_column]
> NULL
> NULL
> value1
> value2
> value3
> or the other way around (ORDER BY `values_column` IS NULL ASC):
> [values_column]
> value1
> value2
> value3
> NULL
> NULL
> I checked JDO 3 specification and found that JDOQL's ordering specification 
> doesn't support specifying NULL values handling:
> ------------------------------------------------------------------------------
> 26.7 Ordering Specification
> This section describes the syntax of the setOrdering argument.
>     OrderingClause:
>         OrderingSpecs ,opt
>     OrderingSpecs:
>         OrderingSpec
>         OrderingSpecs , OrderingSpec
>     OrderingSpec:
>         Expression Ascending
>         Expression Descending
>     Ascending: one of
>         asc ascending
>     Descending: one of
>         desc descending
> Please note, as a usability feature OrderingClause supports an optional 
> trailing comma.
> ------------------------------------------------------------------------------
> Thank you for your time and efforts.



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