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https://issues.apache.org/jira/browse/HIVE-26882?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17822714#comment-17822714
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Peter Vary commented on HIVE-26882:
-----------------------------------
I see this in the MariaDB doc:
https://mariadb.com/kb/en/mariadb-transactions-and-isolation-levels-for-sql-server-users/#isolation-levels-and-locks
{quote}
MariaDB isolation levels differ from SQL Server in the following ways:
REPEATABLE READ does not acquire share locks on all read rows, nor a range lock
on the missing values that match a WHERE clause.
{quote}
Which is not too encouraging. I would expect it to create a lock to prevent
modifications.
When I was working on this I have used 2 clients to connect to the same server,
manually started the transactions, and used queries and updates to check the
actual behavior.
> 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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