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https://issues.apache.org/jira/browse/DERBY-269?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Mamta A. Satoor updated DERBY-269:
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    Derby Info: [Patch Available]

> Provide some way to update index cardinality statistics (e.g. reimplement 
> update statistics)
> --------------------------------------------------------------------------------------------
>
>                 Key: DERBY-269
>                 URL: https://issues.apache.org/jira/browse/DERBY-269
>             Project: Derby
>          Issue Type: New Feature
>          Components: SQL
>    Affects Versions: 10.0.2.0, 10.0.2.1, 10.1.1.0, 10.2.2.0, 10.3.1.4
>            Reporter: Stan Bradbury
>            Assignee: Mamta A. Satoor
>         Attachments: DERBY269_update_statistics_svndiff_ver1.txt, 
> DERBY269_update_statistics_svndiff_ver2.txt, 
> DERBY269_update_statistics_svnstat_ver1.txt, 
> DERBY269_update_statistics_svnstat_ver2.txt
>
>
> Performance problems are being reported that can be resolved by updating the 
> cardinality statistics used by the optimizer.  Currently the only time the 
> statistics are guaranteed to be an up-to-date is when the index is first 
> created on a fully populated table.  This is most easily accomplished on an 
> existing table by using the command: 
>    alter table <table-name> compress [sequential]  
> Compress table is an I/O intensive task.  A better way to achieve this would 
> be to re-enable parser support for the 'update statistics' command or 
> re-implement the update in some other fashion.

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