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Jitendra Nath Pandey commented on HIVE-6664: -------------------------------------------- I have committed this to trunk. [~rhbutani] This bug affects hive-0.13 and causes different results than row-mode execution. This should be fixed in branch-0.13 as well. > Vectorized variance computation differs from row mode computation. > ------------------------------------------------------------------ > > Key: HIVE-6664 > URL: https://issues.apache.org/jira/browse/HIVE-6664 > Project: Hive > Issue Type: Bug > Reporter: Jitendra Nath Pandey > Assignee: Jitendra Nath Pandey > Attachments: HIVE-6664.1.patch, HIVE-6664.1.patch, HIVE-6664.1.patch > > > Following query can show the difference: > select var_samp(ss_sales_price), var_pop(ss_sales_price), > stddev_pop(ss_sales_price), stddev_samp(ss_sales_price) from store_sales. > The reason for the difference is that row mode converts the decimal value to > double upfront to calculate sum of values, when computing variance. But the > vector mode performs local aggregate sum as decimal and converts into double > only at flush. -- This message was sent by Atlassian JIRA (v6.2#6252)