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From "Knut Anders Hatlen (JIRA)" <j...@apache.org>
Subject [jira] Commented: (DERBY-4116) SYSCS_UTIL.SYSCS_UPDATE_STATISTICS should update the store estimated row count for the table
Date Thu, 26 Mar 2009 13:26:57 GMT

    [ https://issues.apache.org/jira/browse/DERBY-4116?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12689472#action_12689472
] 

Knut Anders Hatlen commented on DERBY-4116:
-------------------------------------------

With the latest patch, I think the row count estimate will always be set to 0 if you call
SYSCS_UPDATE_STATISTICS on a table with no indexes, even if the table is not empty. Would
it be possible to initialize rowCount to -1, so that we can detect that the row count was
not calculated, and then add "if (rowCount >= 0)" around the call to setEstimatedRowCount()?

> SYSCS_UTIL.SYSCS_UPDATE_STATISTICS should update the store estimated row count for the
table
> --------------------------------------------------------------------------------------------
>
>                 Key: DERBY-4116
>                 URL: https://issues.apache.org/jira/browse/DERBY-4116
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.5.1.0, 10.6.0.0
>            Reporter: Kathey Marsden
>            Assignee: Kathey Marsden
>         Attachments: derby-4116_diff.txt, derby-4116_diff2.txt
>
>
> When SYSCS_UTIL.SYSCS_UPDATE_STATISTICS is run, it doesn't update the store estimated
row count.  The program oldSelectivity.java attached to DERBY-3955 shows that the statistics
are not updated.
> See discussions in DERBY-3955
> https://issues.apache.org/jira/browse/DERBY-3955?focusedCommentId=12688789&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_12688789
> https://issues.apache.org/jira/browse/DERBY-3955?focusedCommentId=12688813&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_12688813

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