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https://issues.apache.org/jira/browse/HIVE-25867?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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shezm reassigned HIVE-25867:
----------------------------

    Assignee: shezm

> Partition filter condition should pushed down to metastore query if it is 
> equivalence Predicate
> -----------------------------------------------------------------------------------------------
>
>                 Key: HIVE-25867
>                 URL: https://issues.apache.org/jira/browse/HIVE-25867
>             Project: Hive
>          Issue Type: Improvement
>          Components: Standalone Metastore
>            Reporter: shezm
>            Assignee: shezm
>            Priority: Major
>             Fix For: 4.0.0
>
>
> The colnum type of the partition is different from the column type of the hql 
> query, the metastore will not push down the query to the RDBMS, but will 
> instead get all PARTITIONS.PART_NAME of the hive table then filter it 
> according to the hql Expression. 
> https://github.com/apache/hive/blob/5b112aa6dcc4e374c0a7c2b24042f24ae6815da1/standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/MetaStoreDirectSql.java#L1316
> If the hive table has too many partitions and there are multiple hql queries 
> at the same time,RDBMS will increasing CPU IO_WAIT and affect performance.
> If the partition filter condition in hql is an equivalent predicate, the 
> metastore should be pushed down to RDBMS, which can optimize the query 
> performance of hive large tables.



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