[
https://issues.apache.org/jira/browse/PHOENIX-6458?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17386776#comment-17386776
]
ASF GitHub Bot commented on PHOENIX-6458:
-----------------------------------------
kadirozde commented on pull request #1256:
URL: https://github.com/apache/phoenix/pull/1256#issuecomment-886114583
> @lhofhansl ，thank you for reply,
> Yes , I agree that we should check this in because this implemention is
better than existing code which rewrite the sql as `InSubquery`, but I think we
should merge the two different implemention in order to not give user two
different chocies to achieve the same purpose. One way is remove the existing
code and switch to this new implemention, and in the same time , because we
could not make sure the index performs better, we should provide an index hint
(or just use the existing index hint) or config param to disable it.
> And furthermore, we should illustratethat we using index and lookupback in
the `explain`
@Lars already enhanced the explain plan to indicate the server side merge
for uncovered columns in PHOENIX-6409. Regarding to merging this PR and the
existing subquery implementation without creating compatibility issues, it is a
bit tricky for me now. I need to spend time to figure that out. Would you
please create a jira for that? If you like to implement that jira, you would be
more than welcome, @comnetwork.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
> Using global indexes for queries with uncovered columns
> -------------------------------------------------------
>
> Key: PHOENIX-6458
> URL: https://issues.apache.org/jira/browse/PHOENIX-6458
> Project: Phoenix
> Issue Type: Improvement
> Affects Versions: 5.1.0
> Reporter: Kadir Ozdemir
> Priority: Major
> Attachments: PHOENIX-6458.master.001.patch
>
>
> Phoenix client does not use a global index for the queries with the columns
> that are not covered by the global index. However, there are many cases where
> using the global index to map secondary keys to primary keys and then
> retrieving the corresponding rows from the data table results in faster
> queries. It is expected that such performance improvement will happen when
> the index row key prefix length is greater than the data row key prefix
> length for a given query.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
