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https://issues.apache.org/jira/browse/PHOENIX-2221?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15116771#comment-15116771
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Alicia Ying Shu commented on PHOENIX-2221:
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[~jamestaylor] IMHO, when index update failed, the data had been written to the 
data table already. The indexDisableTimestamp was later than the time that the 
data was written to the data table. If we used indexDisableTimestamp as the 
upper point, the data written to the data table had a lower timestamp and would 
be returned from read. 

> Option to make data regions not writable when index regions are not available
> -----------------------------------------------------------------------------
>
>                 Key: PHOENIX-2221
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-2221
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Devaraj Das
>            Assignee: Alicia Ying Shu
>             Fix For: 4.8.0
>
>         Attachments: DelegateIndexFailurePolicy.java, PHOENIX-2221-v1.patch, 
> PHOENIX-2221-v2.patch, PHOENIX-2221-v3.patch, PHOENIX-2221-v4.patch, 
> PHOENIX-2221-v5.patch, PHOENIX-2221-v6.patch, PHOENIX-2221.patch, 
> PHOENIX-2221.wip, PHOENIX-2221_v7.patch
>
>
> In one usecase, it was deemed better to not accept writes when the index 
> regions are unavailable for any reason (as opposed to disabling the index and 
> the queries doing bigger data-table scans).
> The idea is that the index regions are kept consistent with the data regions, 
> and when a query runs against the index regions, one can be reasonably sure 
> that the query ran with the most recent data in the data regions. When the 
> index regions are unavailable, the writes to the data table are rejected. 
> Read queries off of the index regions would have deterministic performance 
> (and on the other hand if the index is disabled, then the read queries would 
> have to go to the data regions until the indexes are rebuilt, and the queries 
> would suffer).



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