[
https://issues.apache.org/jira/browse/HIVE-15397?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15747826#comment-15747826
]
Lefty Leverenz commented on HIVE-15397:
---------------------------------------
Doc note: This changes the default value of *hive.optimize.metadataonly* and
gives it a description. It was created in 0.8.0 by HIVE-1003 and isn't
documented in the wiki yet. Note that the wiki description will need editing
to cover the earlier default value of true.
* [Configuration Properties -- Query and DDL Execution |
https://cwiki.apache.org/confluence/display/Hive/Configuration+Properties#ConfigurationProperties-QueryandDDLExecution]
Added a TODOC2.2 label.
> metadata-only queries may return incorrect results with empty tables
> --------------------------------------------------------------------
>
> Key: HIVE-15397
> URL: https://issues.apache.org/jira/browse/HIVE-15397
> Project: Hive
> Issue Type: Bug
> Reporter: Sergey Shelukhin
> Assignee: Sergey Shelukhin
> Labels: TODOC2.2
> Fix For: 2.2.0
>
> Attachments: HIVE-15397.01.patch, HIVE-15397.patch
>
>
> Queries like select 1=1 from t group by 1=1 may return rows, based on
> OneNullRowInputFormat, even if the source table is empty. For now, add some
> basic detection of empty tables and turn this off by default (since we can't
> know whether a table is empty or not based on there being some files, without
> reading them).
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
