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https://issues.apache.org/jira/browse/OAK-1965?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14064988#comment-14064988
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Jukka Zitting commented on OAK-1965:
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FTR, here's how to use this improvement:
* Assume you have queries with OR constraints containing equality or IN tests
for more than a single property from one selector, like the {{[foo] = 'X' OR
[bar] = 'Y'}} constraint from above. Previously it was not possible to use an
index to speed up the evaluation of such constraints.
* Configure a property index whose {{propertyNames}} list includes all the
properties you expect to use in such queries. For example, a "fooBarIndex" with
{{propertyNames = ['foo', 'bar']}} for the query above.
* With this improvement the property index will automatically detect such an OR
constraint and treat it as an "extended IN" constraint like {{([foo] OR [bar])
IN ('X', 'Y')}} that can be evaluated against the configured index since it
covers the values of both properties.
* To verify that this functionality is indeed in place, you can use the
{{EXPLAIN}} feature or debug logging of the query engine to check that the
query plan mentions "property fooBarIndex IN (foo, bar)" as the index and
constraints being used.
> Support for constraints like: foo = 'X' OR bar = 'Y'
> ----------------------------------------------------
>
> Key: OAK-1965
> URL: https://issues.apache.org/jira/browse/OAK-1965
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: core, query
> Reporter: Jukka Zitting
> Assignee: Jukka Zitting
> Fix For: 1.1
>
>
> Consider the following query statement:
> {noformat}
> SELECT * FROM [nt:base] WHERE [foo] = 'X OR [bar] = 'Y'
> {noformat}
> Such a query could be fairly efficiently executed against a property index
> that indexes the values of both "foo" and "bar" properties. However, the
> query engine doesn't pass such OR constraints down to the index
> implementations, so we currently can't leverage such an index for this query.
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