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https://issues.apache.org/jira/browse/IMPALA-13057?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Joe McDonnell resolved IMPALA-13057.
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Fix Version/s: Impala 4.5.0
Resolution: Fixed
> Incorporate tuple/slot information into the tuple cache key
> -----------------------------------------------------------
>
> Key: IMPALA-13057
> URL: https://issues.apache.org/jira/browse/IMPALA-13057
> Project: IMPALA
> Issue Type: Bug
> Components: Frontend
> Affects Versions: Impala 4.4.0
> Reporter: Joe McDonnell
> Assignee: Joe McDonnell
> Priority: Major
> Fix For: Impala 4.5.0
>
>
> Since the tuple and slot information is kept separately in the descriptor
> table, it does not get incorporated into the PlanNode thrift used for the
> tuple cache key. This means that the tuple cache can't distinguish between
> these two queries:
> {noformat}
> select int_col1 from table;
> select int_col2 from table;{noformat}
> To solve this, the tuple/slot information needs to be incorporated into the
> cache key. PlanNode::initThrift() walks through each tuple, so this is a good
> place to serialize the TupleDescriptor/SlotDescriptors and incorporate it
> into the hash.
> The tuple ids and slot ids are global ids, so the value is influenced by the
> entirety of the query. This is a problem for matching cache results across
> different queries. As part of incorporating the tuple/slot information, we
> should also add an ability to translate tuple/slot ids into ids local to a
> subtree.
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