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https://issues.apache.org/jira/browse/IMPALA-8809?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Gabor Kaszab reassigned IMPALA-8809:
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    Assignee:     (was: Gabor Kaszab)

> Refresh a subset of partitions for ACID tables
> ----------------------------------------------
>
>                 Key: IMPALA-8809
>                 URL: https://issues.apache.org/jira/browse/IMPALA-8809
>             Project: IMPALA
>          Issue Type: Improvement
>          Components: Frontend
>    Affects Versions: Impala 3.3.0
>            Reporter: Gabor Kaszab
>            Priority: Critical
>              Labels: impala-acid
>
> Enhancing REFRESH logic to handle ACID tables was covered by this change: 
> https://issues.apache.org/jira/browse/IMPALA-8600
> Basically each user initiated REFRESH PARTITION is rejected meanwhile the 
> REFRESH_PARTITION event in event processor are actually doing a full table 
> load for ACID tables.
> There is room for improvement: When a full table refresh is being executed on 
> an ACID table we can have 2 scenarios:
> - If there was some schema changes then reload the full table. Identify such 
> a scenario should be possible by checking the table-level writeId. However, 
> there is a bug in Hive that it doesn't update that field for partitioned 
> tables (https://issues.apache.org/jira/browse/HIVE-22062). This would be the 
> desired way but could also be workarounded by checking other fields lik 
> lastDdlChanged or such.
> - If a full table refresh is not needed then we should fetch the 
> partition-level writeIds and reload only the ones that are out-of-date 
> locally.



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