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https://issues.apache.org/jira/browse/PHOENIX-5491?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Chen Feng updated PHOENIX-5491:
-------------------------------
    Priority: Minor  (was: Critical)

> Improve performance of InListExpression.hashCode
> ------------------------------------------------
>
>                 Key: PHOENIX-5491
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-5491
>             Project: Phoenix
>          Issue Type: Improvement
>    Affects Versions: 5.0.0, 4.14.3
>            Reporter: Chen Feng
>            Assignee: Chen Feng
>            Priority: Minor
>         Attachments: PHOENIX-5491-v2.patch, PHOENIX-5491.patch
>
>
> WhereOptimizer runs very slow in parsing sql like "where A in (a1, a2, ..., 
> a_N) and B = X" when N is very large. In our environment, it runs > 90s for N 
> = 140000.
> This is because for the same instance of InListExpression, 
> InListExpression.hashCode() is calculate every time, where 
> InListExpression.values is traversed.
> In previous sql, InListExpression.hashCode() will be called N times, and 
> InListExpression.values has N elements. Therefore the total complexity is N^2.
> Saving the hashCode of InListExpression can reduce the complexity to N. The 
> test shows the large sql can be finished within 5 seconds.



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