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https://issues.apache.org/jira/browse/OAK-8343?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16849694#comment-16849694
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Thomas Mueller commented on OAK-8343:
-------------------------------------

Looks like the query
{noformat}
SELECT * FROM [rep:Authorizable] WHERE [rep:principalName] = $principalName /* 
oak-internal */
{noformat}

is run quite early, and uses the node type index then (cost: 4). I don't know 
yet why the /oak:index/principalName index isn't used at that time, looks like 
it's not available yet.

> Allow queries to be delayed until an index is available
> -------------------------------------------------------
>
>                 Key: OAK-8343
>                 URL: https://issues.apache.org/jira/browse/OAK-8343
>             Project: Jackrabbit Oak
>          Issue Type: Improvement
>          Components: lucene, query
>            Reporter: Thomas Mueller
>            Assignee: Thomas Mueller
>            Priority: Major
>             Fix For: 1.14.0
>
>         Attachments: OAK-8343-b.patch, OAK-8343.patch
>
>
> Currently, indexes are built asynchronously. That is, if an index definition 
> is added, the index is eventually built, but it's quite hard to say when it 
> is ready for queries. This can be specially a problem right after the initial 
> repository initialization, or after an upgrade.
> In theory, system startup could be delayed until all indexes are ready (e.g. 
> set the "reindex" flag for important indexes, and at startup, wait until the 
> "reindex" flag is set to "false"). However, doing that would block threads 
> that _don't_ need an index. It would be better to only block threads that 
> actually do run queries. That would make startup deterministic, without 
> delaying other threads unnecessarily.
> To solve the problem, we can add a property "waitForIndex" in the index 
> definition (just Lucene indexes is fine for now, as those are the important 
> asynchronous ones). If set, then queries that potentially use those indexes 
> are delayed, until the indexes are ready for sure. Reindex would need to 
> remove that property (the same as it removes e.g. refresh or sets reindex to 
> false). For added security, queries are only blocked as long as "reindex" is 
> also set to true (this ensures that waitForIndex is removed eventually), and 
> waiting should time out after 2 minutes, to ensure the feature doesn't block 
> startup forever if indexing fails for some reason.



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