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https://issues.apache.org/jira/browse/IGNITE-11756?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Roman Kondakov reassigned IGNITE-11756:
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    Assignee: Roman Kondakov

> SQL: implement a table row count statistics for the local queries
> -----------------------------------------------------------------
>
>                 Key: IGNITE-11756
>                 URL: https://issues.apache.org/jira/browse/IGNITE-11756
>             Project: Ignite
>          Issue Type: Improvement
>          Components: sql
>            Reporter: Roman Kondakov
>            Assignee: Roman Kondakov
>            Priority: Major
>
> Row count statistics should help the H2 optimizer to select the better query 
> execution plan. Currently the row count supplied to H2 engine is hardcoded 
> value == 10000 (see {{org.h2.index.Index#getRowCountApproximation}}).  As a 
> first step we can provide an actual table size in the case of local query. To 
> prevent counting size on each invocation we can cache row count value and 
> invalidate it in some cases:
>  * Rebalancing
>  * Multiple updates (after the initial loading)
>  * On timeout (i.e. 1 minute)



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