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https://issues.apache.org/jira/browse/IGNITE-28296?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Andrey Mashenkov reassigned IGNITE-28296:
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Assignee: Andrey Mashenkov
> SQL. Prefer table scan for unbounded scan with no sort required.
> ----------------------------------------------------------------
>
> Key: IGNITE-28296
> URL: https://issues.apache.org/jira/browse/IGNITE-28296
> Project: Ignite
> Issue Type: Improvement
> Components: sql ai3
> Reporter: Andrey Mashenkov
> Assignee: Andrey Mashenkov
> Priority: Minor
> Labels: ignite-3
> Fix For: 3.2
>
> Time Spent: 10m
> Remaining Estimate: 0h
>
>
> Assume there is a table with secondary index by some column.
> In the next queries, `val1` is non-indexed column.
> {noformat}
> SELECT * FROM T1 LEFT JOIN T2 ON t1.val1 = t2.val1
> SELECT * FROM T1 ORDER BY val1
> SELECT * FROM T1{noformat}
> As for now, we choose index scan if table size is zero.
> So, we choose more expensive plan with IndexScan, when statistics are not
> available yet.
> The reason is we can got zero cost if IndexScan has no condition.
>
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