[jira] [Commented] (HIVE-6109) Support customized location for EXTERNAL tables created by Dynamic Partitioning

["Satish Mittal (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HIVE-6109?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13893691#comment-13893691 ] 

Satish Mittal commented on HIVE-6109:
-------------------------------------

Copy-pasting my response to review comments from review-board:

1)Sushanth:  "_DYN" is already defined in FosterStorageHandler, needs to have one place where it's defined. I'm okay with it being defined here if the FosterStorageHandler constant is removed and references to that are changed to reference this.

Satish Mittal: Will refactor it now. I didn't want to touch unrelated code in the first cut.

2) Sushanth: whitespace errors - git refers to a bunch of these through the patch when we try to apply, please correct for final patch upload.

Satish Mittal: Will do.

3) Sushanth: A bit about code readability - if we add a special case, then it makes sense to add the special case as an else, rather than as an if - that way, the default behaviour is visible first, and then the special case - please swap this around so that this is a if (!customDynamicLocationUsed) structure.

Satish Mittal: Fine, will do that.

4) Sushanth: This is now significant amount of code repetition from line 720-741 above, please see if we can refactor this into a separate method.

Satish Mittal: I will see if it can be easily refactored into a private method.

5) Sushanth: This becomes the primary API point with this change, wherein, a user that is using HCatOutputFormat will generate an OutputJobInfo, and then call setCustomDynamicLocation on it. This is fine for M/R users of HCat, but is something that will wind up having to be implemented for each M/R user. It might have been better to define a constant in HCatConstants, say "hcat.dynamic.partitioning.custom.pattern", and to use that as a JobInfo parameter. That makes it easier for other tools to integrate with this feature. For example, with your patch, we still do not support the ability for the HCatStorer from pig to be able to write to custom dynamic partitions, while we do want to keep feature parity where possible between HCatOutputFormat and HCatStorer.

In fact, as a design goal for HCat, we're trying to move away from letting(requiring) users explicitly muck around with OutputJobInfo and InputJobInfo, and stick to static calls to HCatInputFormat/HCatOutputFormat.

I would like to see this call be something the HCatOutputFormat automatically calls if a jobConf parameter(as above) is set. That way, we can solve pig compatibility as well easily.

Satish Mittal: Thanks for this feedback Sushanth. I had realized that with the current patch, HCatStorer is still not covered (only M/R jobs are covered), and was thinking of exposing equivalent APIs in HCatStorer to achieve it. However your suggestion sounds cleaner to me. Will do that!

> Support customized location for EXTERNAL tables created by Dynamic Partitioning
> -------------------------------------------------------------------------------
>
>                 Key: HIVE-6109
>                 URL: https://issues.apache.org/jira/browse/HIVE-6109
>             Project: Hive
>          Issue Type: Improvement
>          Components: HCatalog
>            Reporter: Satish Mittal
>            Assignee: Satish Mittal
>         Attachments: HIVE-6109.1.patch.txt, HIVE-6109.2.patch.txt, HIVE-6109.3.patch.txt, HIVE-6109.pdf
>
>
> Currently when dynamic partitions are created by HCatalog, the underlying directories for the partitions are created in a fixed 'Hive-style' format, i.e. root_dir/key1=value1/key2=value2/.... and so on. However in case of external table, user should be able to control the format of directories created for dynamic partitions.



--
This message was sent by Atlassian JIRA
(v6.1.5#6160)