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From "Kathey Marsden (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DERBY-6115) Certain OR expressions are not passed to Table indexes or Table Function initScan()
Date Tue, 22 Oct 2013 16:23:42 GMT

    [ https://issues.apache.org/jira/browse/DERBY-6115?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13801972#comment-13801972
] 

Kathey Marsden commented on DERBY-6115:
---------------------------------------

Is the IN list portion the same as https://issues.apache.org/jira/browse/DERBY-6301 ?

> Certain OR expressions are not passed to Table indexes or Table Function initScan()
> -----------------------------------------------------------------------------------
>
>                 Key: DERBY-6115
>                 URL: https://issues.apache.org/jira/browse/DERBY-6115
>             Project: Derby
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 10.5.1.1, 10.5.2.0, 10.5.3.0, 10.6.1.0, 10.6.2.1, 10.7.1.1, 10.8.1.2,
10.8.2.2, 10.8.3.0, 10.9.1.0, 10.10.1.1
>            Reporter: David Vyvyan
>              Labels: derby_triage10_11
>
> Issue originally posted here:
> ====================
> http://apache-database.10148.n7.nabble.com/RestrictedVTI-initScan-does-not-pass-certain-Table-Functions-predicate-expressions-td128229.html
> Note by Rick Hillegas:
> ================
> Hi David, 
> I think it's worth filing a JIRA for this issue. If the defect is shared 
> by VTIs and table functions then there's a possibility that ordinary 
> table scans suffer from it too. That would raise the problem's urgency. 
> Thanks, 
> -Rick 
> Summary Description:
> ================
> Basically some WHERE clause expressions do not get passed through via RestrictedVTI.initScan().
> This can have a severe impact on memory/performance.
> (I suspect the issue may be related to logic which tries to move AND nodes to the top
of the tree...?)
> Examples (I have a few more here than in the post above):
> These get passed ok in the Restriction object:
> - C1>6
> - C1>1 AND C2<'d'
> - C1>6 OR C2<'d'
> - C1>1 AND (C1<6 OR C2<'d')
> This one gets passed partially by initScan():
> C1>1 AND (C1<6 OR (C2>'e' AND C2<'d'))    ===>    initScan() passes only:
 "C1" > 1
> These do not get passed at all (initScan() Restriction argument object is null):
> - C1>6 OR (C1>1 AND C2<'d')
> - C1>6 OR ((C1>1 AND C2<'d') AND C2>'b')
> - C1 in ( 1, 4 )
> - C1 in ( 1, 4 ) OR C2>'f' -- Can Derby resolve in() clauses to a list of '=' conditions
? This would be useful!
> My table function is defined as follows:
> CREATE FUNCTION TF_TEST1() RETURNS TABLE(C1 INT, C2 VARCHAR(32672)) PARAMETER STYLE DERBY_JDBC_RESULT_SET
LANGUAGE JAVA NOT DETERMINISTIC READS SQL DATA EXTERNAL NAME 'core.TestTableFunctions.TF_TEST1'



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