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Ron Bodkin commented on HIVE-2116: ---------------------------------- Table b was an HBase table, rather than a traditional HDFS file, if that is relevant to the issue. > Optimize map-side scans for right-side of join > ---------------------------------------------- > > Key: HIVE-2116 > URL: https://issues.apache.org/jira/browse/HIVE-2116 > Project: Hive > Issue Type: Improvement > Reporter: Ron Bodkin > > I had a large query like select * from a join b on a.key=b.key where...; > Table b was too large, so I attempted to optimize by adding constraints on b > to the where clause, e.g., > where b.size>=mn and b.size<=mx and ...; > However, the Hive 0.8.0 optimizer pushed the constraint on b into the reduce > phase (defeating its purpose). > I was able to force Hive to run the optimization map-side by this workaround: > join (select * from b where size>=mn and size<=mx) b on a.key=b.key where ...; > But it would be nice for Hive to pull filters on joined records into the map > phase where possible. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira