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https://issues.apache.org/jira/browse/HIVE-26882?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17825557#comment-17825557
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Rui Li commented on HIVE-26882:
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bq. I'm trying to suggest to use the direct SQL to update the metadata location 
only, and keep the other parts of the code intact. I think this would be enough 
to prevent concurrent updates of the table.
Yes, but that requires the direct SQL and JDO run in the same transaction, 
right? Otherwise the update will not be atomic. I'm not very familiar with JDO. 
Does {{PersistenceManager::newQuery}} guarantees the query shares the same 
transaction?

> Allow transactional check of Table parameter before altering the Table
> ----------------------------------------------------------------------
>
>                 Key: HIVE-26882
>                 URL: https://issues.apache.org/jira/browse/HIVE-26882
>             Project: Hive
>          Issue Type: Improvement
>          Components: Standalone Metastore
>            Reporter: Peter Vary
>            Assignee: Peter Vary
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 2.3.10, 4.0.0-beta-1
>
>          Time Spent: 4h 40m
>  Remaining Estimate: 0h
>
> We should add the possibility to transactionally check if a Table parameter 
> is changed before altering the table in the HMS.
> This would provide an alternative, less error-prone and faster way to commit 
> an Iceberg table, as the Iceberg table currently needs to:
> - Create an exclusive lock
> - Get the table metadata to check if the current snapshot is not changed
> - Update the table metadata
> - Release the lock
> After the change these 4 HMS calls could be substituted with a single alter 
> table call.
> Also we could avoid cases where the locks are left hanging by failed processes



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