[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 resolved TEIID-5700.
-----------------------------------
    Resolution: Done


The dependent join back-off calculation was updated to use the ndv value calculated based upon the quick search.  This will generally be much higher than the previous value which was just the independent value ndv.

> 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.



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