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https://issues.apache.org/jira/browse/HIVE-16813?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16041234#comment-16041234
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Sankar Hariappan commented on HIVE-16813:
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[~anishek]
{quote}
One additional use case as i was going through the patch, though not related to
incremental load but to bootstrap load. Currently during bootstrap load we dont
order tables in a database in any specific order, hence if there is a
virtual_view/table which is created using a select as and the table which its
selected from is dumped after, there might be a failure, unfortunately i was
not able to test the same as replication related commands are not working on my
machine since distcp doAs is not able to impersonate.
{quote}
I think, for bootstrap, table dump sequence won't be a problem even if table is
created using CTAS as the resultant table or view will be an independent
object.
- CTAS will create an independent table with schema and data cloned from the
original table. But, once the table is created, it has no backward reference.
- In case of virtual views, the reference query command is just stored into the
Table object corresponding to the view. During dump/load, no computations done
using this query command. Hence, no reference to the original table unless
someone issue a query on the view.
- For materialized views, it is as good as an independent table with own schema
and data files. Even queries won't refer back to the original table.
> Incremental REPL LOAD should load the events in the same sequence as it is
> dumped.
> ----------------------------------------------------------------------------------
>
> Key: HIVE-16813
> URL: https://issues.apache.org/jira/browse/HIVE-16813
> Project: Hive
> Issue Type: Sub-task
> Components: Hive, repl
> Affects Versions: 2.1.0
> Reporter: Sankar Hariappan
> Assignee: Sankar Hariappan
> Labels: DR, replication
> Attachments: HIVE-16813.01.patch, HIVE-16813.02.patch
>
>
> Currently, incremental REPL DUMP use $dumpdir/<eventID> to dump the metadata
> and data files corresponding to the event. The event is dumped in the same
> sequence in which it was generated.
> Now, REPL LOAD, lists the directories inside $dumpdir using listStatus and
> sort it using compareTo algorithm of FileStatus class which doesn't check the
> length before sorting it alphabetically.
> Due to this, the event-100 is processed before event-99 and hence making the
> replica database non-sync with source.
> Need to use a customized compareTo algorithm to sort the FileStatus.
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