Ok we are talking about bucket pruning here
What version of Hive are using? Bucket pruning I believe is available from version 2.0 HTH Dr Mich Talebzadeh LinkedIn <https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw> https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw Sybase ASE 15 Gold Medal Award 2008 A Winning Strategy: Running the most Critical Financial Data on ASE 15 <http://login.sybase.com/files/Product_Overviews/ASE-Winning-Strategy-091908.pdf> http://login.sybase.com/files/Product_Overviews/ASE-Winning-Strategy-091908.pdf Author of the books "A Practitioner’s Guide to Upgrading to Sybase ASE 15", ISBN 978-0-9563693-0-7. co-author "Sybase Transact SQL Guidelines Best Practices", ISBN 978-0-9759693-0-4 Publications due shortly: Complex Event Processing in Heterogeneous Environments, ISBN: 978-0-9563693-3-8 Oracle and Sybase, Concepts and Contrasts, ISBN: 978-0-9563693-1-4, volume one out shortly <http://talebzadehmich.wordpress.com/> http://talebzadehmich.wordpress.com NOTE: The information in this email is proprietary and confidential. This message is for the designated recipient only, if you are not the intended recipient, you should destroy it immediately. Any information in this message shall not be understood as given or endorsed by Peridale Technology Ltd, its subsidiaries or their employees, unless expressly so stated. It is the responsibility of the recipient to ensure that this email is virus free, therefore neither Peridale Technology Ltd, its subsidiaries nor their employees accept any responsibility. From: Akansha Jain [mailto:akansha.15au...@gmail.com] Sent: 22 January 2016 21:55 To: user@hive.apache.org Subject: Hive Bucketing Hi All, I have enabled bucketing in table. I created 256 buckets on user id. Now when I am querying (select count(*) from table where userid =172839393) that table, map reduce should only use single partitioned file as input to mappers. But its considering all files as input to mapper and I don't see any performance benefit when I run same query in unbucketed table. Do I have to set any property before running queries on bucketed tables. I tried join query also, but no performance improvement. In fact, I think it's taking few more seconds as compared to unbucketed table. Thanks, AJ
