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https://issues.apache.org/jira/browse/HIVE-18192?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16333960#comment-16333960
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Sankar Hariappan commented on HIVE-18192:
-----------------------------------------

Attached 04.patch after rebasing with master.

> Introduce WriteID per table rather than using global transaction ID
> -------------------------------------------------------------------
>
>                 Key: HIVE-18192
>                 URL: https://issues.apache.org/jira/browse/HIVE-18192
>             Project: Hive
>          Issue Type: Sub-task
>          Components: HiveServer2, Transactions
>    Affects Versions: 3.0.0
>            Reporter: anishek
>            Assignee: Sankar Hariappan
>            Priority: Major
>              Labels: ACID, DR, pull-request-available
>             Fix For: 3.0.0
>
>         Attachments: HIVE-18192.01.patch, HIVE-18192.02.patch, 
> HIVE-18192.03.patch
>
>
> To support ACID replication, we will be introducing a per table write Id 
> which will replace the transaction id in the primary key for each row in a 
> ACID table.
> The current primary key is determined via 
>  <original transaction id, bucketid , rowid>
> which will move to 
>  <original write id, bucketid, rowid>
> For each table modified by the given transaction will have a table level 
> write ID allocated and a persisted map of global txn id -> to table -> write 
> id for that table has to be maintained to allow Snapshot isolation.
> Readers should use the combination of ValidTxnList and 
> ValidWriteIdList(Table) for snapshot isolation.
>  
>  [Hive Replication - ACID 
> Tables.pdf|https://issues.apache.org/jira/secure/attachment/12903157/Hive%20Replication-%20ACID%20Tables.pdf]
>  has a section "Per Table Sequences (Write-Id)" with more detials



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