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Gopal V commented on HIVE-9644: ------------------------------- LGTM - +1. [~ashutoshc]: can you file a bug for the StatsOptimizer row-schema issue - that's generating sub-optimal reducer counts with this patch, but qualifies for a different JIRA. > Fold case & when udfs > --------------------- > > Key: HIVE-9644 > URL: https://issues.apache.org/jira/browse/HIVE-9644 > Project: Hive > Issue Type: Bug > Components: Logical Optimizer > Affects Versions: 0.14.0, 1.0.0, 1.1.0 > Reporter: Gopal V > Assignee: Ashutosh Chauhan > Attachments: HIVE-9644.1.patch, HIVE-9644.2.patch, HIVE-9644.3.patch, > HIVE-9644.patch > > > Constant folding for queries don't kick in for some automatically generated > query patterns which look like this. > {code} > hive> explain select count(1) from store_sales where (case ss_sold_date when > '1998-01-01' then 1 else null end)=1; > {code} > This should get rewritten by pushing the equality into the case branches. > {code} > select count(1) from store_sales where (case ss_sold_date when '1998-01-01' > then 1=1 else null=1 end); > {code} > Ending up with a simplified filter condition, resolving itself as > {code} > select count(1) from store_sales where ss_sold_date= '1998-01-01' ; > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)