[teiid-issues] [JBoss JIRA] (TEIID-5700) Dependent join back-off max ndv set to independent ndv estimate

[Steven Hawkins (Jira)]

     [ https://issues.jboss.org/browse/TEIID-5700?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Steven Hawkins updated TEIID-5700:
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    Workaround Description: Set the cardinality value of the independent side table(s) to a higher value to allow the dependent join to proceed.


> Dependent join back-off max ndv set to independent ndv estimate
> ---------------------------------------------------------------
>
>                 Key: TEIID-5700
>                 URL: https://issues.jboss.org/browse/TEIID-5700
>             Project: Teiid
>          Issue Type: Bug
>          Components: Query Engine
>            Reporter: Steven Hawkins
>            Assignee: Steven Hawkins
>            Priority: Major
>             Fix For: 12.2, 11.2.3, 12.1.1
>
>
> The search being used to find a max ndv for the independent side is just setting the result to be the original ndv estimate for the independent side.  This results in unnecessary back-offs of performing the dependent join with a log message similar to:
> TEIID30011 Not performing dependent join using source $dsc/id0, since the number of distinct rows for expression g0.fkIdProductCode exceeds 1.333.  You should ensure that your source statistics, including column distinct value counts, accurately reflect the source or use a MAKE_DEP hint to force the join.



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