[jira] [Assigned] (IMPALA-7878) Bad SQL generated by compute incremental stats

["Fang-Yu Rao (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-7878?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Fang-Yu Rao reassigned IMPALA-7878:
-----------------------------------

    Assignee: Fang-Yu Rao

> Bad SQL generated by compute incremental stats 
> -----------------------------------------------
>
>                 Key: IMPALA-7878
>                 URL: https://issues.apache.org/jira/browse/IMPALA-7878
>             Project: IMPALA
>          Issue Type: Improvement
>          Components: Frontend
>            Reporter: Pooja Nilangekar
>            Assignee: Fang-Yu Rao
>            Priority: Major
>
> Computing incremental stats on partitions generates bad sql for instance: 
> For a table foo partitioned by column bar, the compute stats statement:
> {code:java}
> compute incremental stats foo partition (bar = 1); 
> {code}
> would generate the following query: 
> {code:java}
> SELECT COUNT(*), month FROM foo WHERE (bar=1) GROUP BY bar;
> {code}
> If this were to be rewritten as follows, it would produce fewer fragments and hence also reduce query memory by avoiding a hash aggregation node. 
> {code:java}
> SELECT COUNT(*), 1 FROM foo WHERE bar=1; 
> {code}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org