[
https://issues.apache.org/jira/browse/HIVE-10636?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14543883#comment-14543883
]
Ashutosh Chauhan commented on HIVE-10636:
-----------------------------------------
[~gopalv] Thanks for review. You are spot on. I also thought about this one
and actually have this implemented in earlier version of this patch (
HIVE-10636.1.patch). If you look at that patch for fold_when.q.out changes
amounts to exactly this. Thinking more on this, I retracted this change in
later versions of patch. Reason being this folding is safe only in context of
Filter Operator. If such a case expression appears in select clause, this is
invalid, because there false != null.
Currently, shortcutFunction() doesn't know whether its a part of select or
filter operator. So, to achieve above needs more changes with passing the
context of operator to function. So, to stop further growth of patch, I removed
those changes. If you think this is a common enough case that we should fold,
let me know I can take a look at this in a follow-up jira.
Committed current patch to master.
> CASE comparison operator rotation optimization
> ----------------------------------------------
>
> Key: HIVE-10636
> URL: https://issues.apache.org/jira/browse/HIVE-10636
> Project: Hive
> Issue Type: New Feature
> Components: Logical Optimizer
> Affects Versions: 0.14.0, 1.0.0, 1.2.0, 1.1.0
> Reporter: Ashutosh Chauhan
> Assignee: Ashutosh Chauhan
> Attachments: HIVE-10636.1.patch, HIVE-10636.2.patch,
> HIVE-10636.3.patch, HIVE-10636.patch
>
>
> Step 1 as outlined in description of HIVE-9644
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
