Sergey Shelukhin commented on HIVE-12631:

Sorry, a couple more comments on RB.

> LLAP: support ORC ACID tables
> -----------------------------
>                 Key: HIVE-12631
>                 URL: https://issues.apache.org/jira/browse/HIVE-12631
>             Project: Hive
>          Issue Type: Bug
>          Components: llap, Transactions
>            Reporter: Sergey Shelukhin
>            Assignee: Teddy Choi
>         Attachments: HIVE-12631.10.patch, HIVE-12631.10.patch, 
> HIVE-12631.11.patch, HIVE-12631.11.patch, HIVE-12631.12.patch, 
> HIVE-12631.13.patch, HIVE-12631.15.patch, HIVE-12631.16.patch, 
> HIVE-12631.17.patch, HIVE-12631.18.patch, HIVE-12631.19.patch, 
> HIVE-12631.1.patch, HIVE-12631.20.patch, HIVE-12631.21.patch, 
> HIVE-12631.22.patch, HIVE-12631.23.patch, HIVE-12631.24.patch, 
> HIVE-12631.25.patch, HIVE-12631.26.patch, HIVE-12631.2.patch, 
> HIVE-12631.3.patch, HIVE-12631.4.patch, HIVE-12631.5.patch, 
> HIVE-12631.6.patch, HIVE-12631.7.patch, HIVE-12631.8.patch, 
> HIVE-12631.8.patch, HIVE-12631.9.patch
> LLAP uses a completely separate read path in ORC to allow for caching and 
> parallelization of reads and processing. This path does not support ACID. As 
> far as I remember ACID logic is embedded inside ORC format; we need to 
> refactor it to be on top of some interface, if practical; or just port it to 
> LLAP read path.
> Another consideration is how the logic will work with cache. The cache is 
> currently low-level (CB-level in ORC), so we could just use it to read bases 
> and deltas (deltas should be cached with higher priority) and merge as usual. 
> We could also cache merged representation in future.

This message was sent by Atlassian JIRA

Reply via email to