[
https://issues.apache.org/jira/browse/PHOENIX-6899?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17698554#comment-17698554
]
ASF GitHub Bot commented on PHOENIX-6899:
-----------------------------------------
tkhurana merged PR #1578:
URL: https://github.com/apache/phoenix/pull/1578
> Query limit not enforced in UncoveredIndexRegionScanner
> -------------------------------------------------------
>
> Key: PHOENIX-6899
> URL: https://issues.apache.org/jira/browse/PHOENIX-6899
> Project: Phoenix
> Issue Type: Improvement
> Affects Versions: 5.2.0, 5.1.3
> Reporter: Tanuj Khurana
> Assignee: Tanuj Khurana
> Priority: Major
>
> If the select query specifies a limit, the limit is available as a scan
> attribute BaseScannerRegionObserver.INDEX_LIMIT
> (https://github.com/apache/phoenix/blob/master/phoenix-core/src/main/java/org/apache/phoenix/iterate/RegionScannerFactory.java#L154).
> However, that limit is not enforced on the page size used in the
> UncoveredIndexRegionScanner. It continues to use the page size based on the
> config *_phoenix.index.page_size_in_rows_*
> This results in doing extra work in reading the index rows and then joining
> them with the data table only to be thrown away. Set the page size to be the
> smaller of the configured size and the query limit if provided.
> Another thing I found was that the explain plan when the uncovered index is
> used doesn't list the plan step "*SERVER <> ROW LIMIT*"
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
