db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Thomas Nielsen (JIRA)" <j...@apache.org>
Subject [jira] Commented: (DERBY-2998) Add support for ROW_NUMBER() window function
Date Mon, 03 Mar 2008 19:12:50 GMT

    [ https://issues.apache.org/jira/browse/DERBY-2998?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12574678#action_12574678
] 

Thomas Nielsen commented on DERBY-2998:
---------------------------------------

Army> "pointsToWindowFunction()" in ColumnReference.java is no longer called. Would it
make sense to remove the method altogether? 

Yes - it should be removed. Will fix tomorrow.

Army>  .... And if so, do you happen to know if this change to RealDistinctScanStatistics
will still be needed after the DISTINCT issue is resolved?

Fixing the distinct with a window function issue will result in placing the distinct node
on top of the window node(s). Today it's the other way around. To do so involves explicitly
doing a normal scan and a distinct sort - like you say. So, yes, we might not actually need
it - please don't commit it yet.

I'll start on the distinct fix tomorrow. The fix I tried in my sandbox worked for non-nested
queries, but not when there's a subquery with a window function. This resulted in incorrect
results being returned. Looked like a column mapping issue in the distinct node from the couple
of alternative queries I tried without a window function. I know where to start looking at
least :)

> Add support for ROW_NUMBER() window function
> --------------------------------------------
>
>                 Key: DERBY-2998
>                 URL: https://issues.apache.org/jira/browse/DERBY-2998
>             Project: Derby
>          Issue Type: Sub-task
>          Components: SQL
>            Reporter: Thomas Nielsen
>            Assignee: Thomas Nielsen
>            Priority: Minor
>         Attachments: d2998-10.diff, d2998-10.stat, d2998-11.diff, d2998-12.diff, d2998-12.stat,
d2998-13.diff, d2998-13.stat, d2998-14.diff, d2998-14.stat, d2998-15.diff, d2998-15.stat,
d2998-16.diff, d2998-16.stat, d2998-17.diff, d2998-17.stat, d2998-18.diff, d2998-18.stat,
d2998-19.diff, d2998-19.stat, d2998-4.diff, d2998-4.stat, d2998-5.diff, d2998-5.stat, d2998-6.diff,
d2998-6.stat, d2998-7.diff, d2998-7.stat, d2998-8.diff, d2998-8.stat, d2998-9-derby.log, d2998-9.diff,
d2998-9.stat, d2998-doc-1.diff, d2998-doc-1.stat, d2998-doc-2.diff, d2998-doc-2.stat, d2998-followup-2.diff,
d2998-followup-2.stat, d2998-followup-issue1.diff, d2998-followup-issue1.stat, d2998-followup-issue4.diff,
d2998-followup-issue4.stat, d2998-followup-queryplanAOOB.diff, d2998-followup-queryplanAOOB.stat,
d2998-followup-testsuite.diff, d2998-followup-testsuite.stat, d2998-test.diff, d2998-test.stat,
d2998-test2.diff, d2998-test2.stat, d2998-test3.diff, d2998-test3.stat, d2998-test4.diff,
d2998-test4.stat, d2998-test6.diff, d2998-test7.diff, d2998-test8.diff, d2998-test9.diff
>
>
> As part of implementing the overall OLAP Operations features of SQL (DERBY-581), implement
the ROW_NUMBER() window function.
> More information about this feature is available at http://wiki.apache.org/db-derby/OLAPRowNumber

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message