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https://issues.apache.org/jira/browse/OAK-2081?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Amit Jain updated OAK-2081:
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Priority: Minor (was: Major)
> [Ordered Index] Incorrect index plan selection
> -----------------------------------------------
>
> Key: OAK-2081
> URL: https://issues.apache.org/jira/browse/OAK-2081
> Project: Jackrabbit Oak
> Issue Type: Bug
> Components: query
> Reporter: Amit Jain
> Priority: Minor
> Attachments: OAK-2081.patch
>
>
> When an ordered index is defined on multiple properties the plan selection
> seems to be incorrect. There are a few potential problems :
> * For > or < conditions, the cost is doubled because of incorrect condition
> in {{OrderedContentMirrorStoreStrategy#count}}. The condition should be
> {{cost >= max}} instead of {{count > max}}
> * If multiple properties are specified in the index definition, only the
> first property is indexed and others ignored. IMO only the first should be
> used when selecting the plan in
> {{OrderedPropertyIndexLookup#getIndexNode()}}, otherwise it may happen that
> the property restriction that is not indexed is used for the index plan.
> * In {{QueryImpl#getBestSelectorExecutionPlan}} limit is used to damp the
> cost which does not look right. E.g. limit is set to 10 and 2 plans with cost
> 190 and 110 are candidates, the plan ultimately selected out of the 2 after
> damping with the limit will be arbitrary (the first to be processed) as the
> actual estimated cost is effectively ignored.
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