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Gopal V commented on HIVE-7832: ------------------------------- I left some minor comments on RB - the extra configuration variable is not really a user-friendly feature and needs to be removed. Possibly provide a hard enable/disable config variable and nothing more around this. > Do ORC dictionary check at a finer level and preserve encoding across stripes > ----------------------------------------------------------------------------- > > Key: HIVE-7832 > URL: https://issues.apache.org/jira/browse/HIVE-7832 > Project: Hive > Issue Type: Improvement > Affects Versions: 0.14.0 > Reporter: Prasanth J > Assignee: Prasanth J > Attachments: HIVE-7832.1.patch, HIVE-7832.2.patch, HIVE-7832.3.patch, > HIVE-7832.4.patch, HIVE-7832.5.patch, HIVE-7832.6.patch, HIVE-7832.7.patch > > > Currently ORC dictionary check happens while writing the stripe. Just before > writing stripe if ratio of dictionary entries to total non-null rows is > greater than threshold then the dictionary is discarded. Also, the decision > of using dictionary or not is preserved across stripes. This sometimes leads > to costly insertion cost of O(logn) for each stripes when there are too many > distinct keys. -- This message was sent by Atlassian JIRA (v6.2#6252)