[
https://issues.apache.org/jira/browse/HIVE-11573?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14716252#comment-14716252
]
Lefty Leverenz commented on HIVE-11573:
---------------------------------------
Doc note: This adds two configuration parameters
(*hive.optimize.point.lookup.min* and *hive.optimize.point.lookup.extract*) to
HiveConf.java, so they need to be documented in Configuration Properties.
* [Configuration Properties -- Query and DDL Execution |
https://cwiki.apache.org/confluence/display/Hive/Configuration+Properties#ConfigurationProperties-QueryandDDLExecution]
> PointLookupOptimizer can be pessimistic at a low nDV
> ----------------------------------------------------
>
> Key: HIVE-11573
> URL: https://issues.apache.org/jira/browse/HIVE-11573
> Project: Hive
> Issue Type: Bug
> Affects Versions: 2.0.0
> Reporter: Gopal V
> Assignee: Gopal V
> Labels: TODOC2.0
> Fix For: 2.0.0
>
> Attachments: HIVE-11573.1.patch, HIVE-11573.2.patch,
> HIVE-11573.3.patch, HIVE-11573.4.patch, HIVE-11573.5.patch, HIVE-11573.6.patch
>
>
> The PointLookupOptimizer can turn off some of the optimizations due to its
> use of tuple IN() clauses.
> Limit the application of the optimizer for very low nDV cases and extract the
> sub-clause as a pre-condition during runtime, to trigger the simple column
> predicate index lookups.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
