[jira] [Commented] (OAK-7739) Use an index only if a certain node or property exists

["Thomas Mueller (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/OAK-7739?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16877894#comment-16877894 ] 

Thomas Mueller commented on OAK-7739:
-------------------------------------

documented in r1862482.

> Use an index only if a certain node or property exists
> ------------------------------------------------------
>
>                 Key: OAK-7739
>                 URL: https://issues.apache.org/jira/browse/OAK-7739
>             Project: Jackrabbit Oak
>          Issue Type: Improvement
>          Components: indexing, query
>            Reporter: Thomas Mueller
>            Priority: Major
>             Fix For: 1.10.0, 1.9.9
>
>
> Currently, adding a new index (or reindexing) means the index is used for queries as soon as indexing is finished. When using the composite node store (in a blue-green deployment), it would be better if there is some control on when the index is used for queries. Meaning, the index is used only if a certain node or property exists. It is not used if the node or property doesn't exist. That allows to control usage as follows:
> * Old (blue) version: node /library/version, property v1 does exist, but v2 does not.
> * New (green) version: node /library/version, property v1 does not exist, but v2 does exist.
> Now a new index can be created which is not used with the old version, but used with the new version. The index configuration is as follows:
> {noformat}
> /oak:index/foo_v2/@useIfExists = /library/version/@v2
> {noformat}
> Similary, an index is used only with the old, but not with the new version, as follows:
> {noformat}
> /oak:index/foo_v1/@useIfExists = /library/version/@v1
> {noformat}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)