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https://issues.apache.org/jira/browse/PHOENIX-4999?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16669424#comment-16669424
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Bin Shi commented on PHOENIX-4999:
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If we agree that we eventually should support it (may be after Alpha), I'm open
to disable it for now. How about making it configurable?
I didn't mean relying on the client side to keep track of data drifts, instead:
# We should have dashboards to show data drift per tenant/table/index. That
dashboard is possibly exposed to customer.
# If we don't allow customer to issue "Update Statistics" command, our system
should do it either periodically or auto triggering based on data drift. Both
Update Statistics and MR jobs need to support Updating Stats on tenant level or
with a particular given key range.
> Update statistics should not be allowed on tenant specific connection
> ---------------------------------------------------------------------
>
> Key: PHOENIX-4999
> URL: https://issues.apache.org/jira/browse/PHOENIX-4999
> Project: Phoenix
> Issue Type: Bug
> Reporter: Karan Mehta
> Assignee: Karan Mehta
> Priority: Major
>
> Update statistics sql would can trigger partial stats collection when ran
> using a tenant specific connection. Originally, update statistics internally
> runs scans on all the regions of table. TenantId field bounds the scans on
> startKey and endKey in tenant specific connection, which can cause stats to
> run only on specific regions and result in partial stats collection.
> Since the view data and table data reside in the same physical HBase table,
> it doesn't make sense to allow users to run stats for specific tenants as
> tenants may span across regions. The issue was first identified in
> PHOENIX-4333.
> The patch however doesn't fully stop the SQL from running. Multiple
> approaches can be taken here.
> # Unset the tenantId on the connection before update statistics is run and
> reset it back later. This can be tricky and bad to implement since tenantId
> is essentially a final field on PhoenixConnection.
> # As [~tdsilva] pointed out, we can throw an UnsupportedOperationException()
> whenever user tries to update statistics on tenant specific connection.
> The second option seems straightforward to implement and can prevent
> accidental usage of this sql.
> [~Bin Shi] [~sukumaddineni] Any thoughts here?
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