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https://issues.apache.org/jira/browse/KYLIN-4315?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Shao Feng Shi resolved KYLIN-4315.
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    Resolution: Fixed

> Use metadata numRows in beeline client for quick row counting
> -------------------------------------------------------------
>
>                 Key: KYLIN-4315
>                 URL: https://issues.apache.org/jira/browse/KYLIN-4315
>             Project: Kylin
>          Issue Type: Improvement
>          Components: Job Engine
>            Reporter: Congling Xia
>            Assignee: Congling Xia
>            Priority: Major
>             Fix For: v3.1.0
>
>
> Hi, I find that in `BeelineHiveClient`, method `getHiveTableRows` uses 
> "select count(*) from <tb_name>" for table row counting. The method is 
> invoked in flat intermediate table redistribution step in cube building.
> This stats can be loaded in metastore. It costs much less time than scanning 
> all rows in Hive table. Since intermediate tables are created and inserted by 
> Kylin, statistics will be automatically calculated and stored in metastore 
> when 
> `[hive.stats.autogather|https://cwiki.apache.org/confluence/display/Hive/Configuration+Properties#ConfigurationProperties-hive.stats.autogather]`
>  is enabled (which is the default setting for Hive). 
> ref Hive wiki for more detail about `numRows` stats: 
> [https://cwiki.apache.org/confluence/display/Hive/StatsDev#StatsDev-ExistingTables%E2%80%93ANALYZE]



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