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From "Harshvardhan Gupta (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DERBY-6938) Obtain cardinality estimates and true estimates for base tables as well as for intermediate results for queries involving multiple joins.
Date Sun, 11 Jun 2017 18:49:19 GMT

    [ https://issues.apache.org/jira/browse/DERBY-6938?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16046055#comment-16046055
] 

Harshvardhan Gupta commented on DERBY-6938:
-------------------------------------------

Hi Bryan,

I am trying to understand the cardinality estimates Derby Optimizer makes in the presence
of joins, I am currently doing more experiments starting from joins for 2 tables and then
moving to more levels of joins similar to those present in job query dataset. Along with this
I am examining the code and will share the information that I obtain here.

Regards,
Vardhan,

>  Obtain cardinality estimates and true estimates for base tables as well as for intermediate
results for queries involving multiple joins. 
> -------------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: DERBY-6938
>                 URL: https://issues.apache.org/jira/browse/DERBY-6938
>             Project: Derby
>          Issue Type: Sub-task
>          Components: SQL
>            Reporter: Harshvardhan Gupta
>            Assignee: Harshvardhan Gupta
>         Attachments: explain.txt
>
>




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