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https://issues.apache.org/jira/browse/OAK-1263?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13922322#comment-13922322
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Alex Parvulescu commented on OAK-1263:
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bq. as long as the index is not defined there should be no problems.
Yes the index editor will not pick up any changes, but for the query index
provider it's a different story.
The _OrderedPropertyIndexProvider_ has the OSGi annotations so it will be
picked up, and the provided _OrderedPropertyIndex_ will inherit the cost so it
will respond with the same value as a regular property index, making the query
engine choose the first one of the two that comes up in the list, and given the
dynamic state of the OSGi whiteboard, the outcome is unpredictable.
> optimize oak index to support 'fast ORDER BY' queries to support sorting &
> pagination for large set of children
> ---------------------------------------------------------------------------------------------------------------
>
> Key: OAK-1263
> URL: https://issues.apache.org/jira/browse/OAK-1263
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: query
> Affects Versions: 0.12
> Reporter: Stefan Egli
> Assignee: Thomas Mueller
> Fix For: 0.19
>
> Attachments: OAK-1263-r1.patch, OAK-1263-r1a.patch,
> OAK-1263-r1b.patch, OAK-1263-r1c.patch, OAK-1263-r1d.patch,
> benchmark-20140228112150.log, benchmark-20140228120718.log,
> benchmark-20140228125248.log
>
>
> We have a use case where we'd like to be able to use an index in a
> "pagination-like" fashion. That is, we'd like to be able to have an index on
> a subtree on a certain property, and then run a query which does ORDER BY
> that property combined with OFFSET. That way, essentially allowing pagination
> of child nodes of a particular parent based on 'sorted by a certain property'.
> AFAIU currently the oak index is not optimized to support ORDER BY queries in
> a fast manner. The index keeps 'the child nodes unsorted', ie to process an
> ORDER BY, the child nodes would have to be 'manually sorted' which can result
> in bad performance given a large number of child nodes.
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