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https://issues.apache.org/jira/browse/HIVE-25589?focusedWorklogId=775003&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-775003
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ASF GitHub Bot logged work on HIVE-25589:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 26/May/22 11:22
Start Date: 26/May/22 11:22
Worklog Time Spent: 10m
Work Description: kasakrisz merged PR #3266:
URL: https://github.com/apache/hive/pull/3266
Issue Time Tracking
-------------------
Worklog Id: (was: 775003)
Time Spent: 1h (was: 50m)
> SQL: Implement HAVING/QUALIFY predicates for ROW_NUMBER()=1
> -----------------------------------------------------------
>
> Key: HIVE-25589
> URL: https://issues.apache.org/jira/browse/HIVE-25589
> Project: Hive
> Issue Type: Improvement
> Components: CBO, SQL
> Affects Versions: 4.0.0
> Reporter: Gopal Vijayaraghavan
> Assignee: Krisztian Kasa
> Priority: Major
> Labels: pull-request-available
> Time Spent: 1h
> Remaining Estimate: 0h
>
> The insert queries which use a row_num()=1 function are inconvenient to write
> or port from an existing workload, because there is no easy way to ignore a
> column in this pattern.
> {code}
> INSERT INTO main_table
> SELECT * from duplicated_table
> QUALIFY ROW_NUMER() OVER (PARTITION BY event_id) = 1;
> {code}
> needs to be rewritten into
> {code}
> INSERT INTO main_table
> select event_id, event_ts, event_attribute, event_metric1, event_metric2,
> event_metric3, event_metric4, .., event_metric43 from
> (select *, ROW_NUMBER() OVER (PARTITION BY event_id) as rnum from
> duplicated_table)
> where rnum=1;
> {code}
> This is a time-consuming and error-prone rewrite (dealing with a messed up
> order of columns between one source and dest table).
> An alternate rewrite would be to do the same or similar syntax using HAVING.
> {code}
> INSERT INTO main_table
> SELECT * from duplicated_table
> HAVING ROW_NUMER() OVER (PARTITION BY event_id) = 1;
> {code}
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