Jitendra Nath Pandey created HIVE-6664:
------------------------------------------
Summary: 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
Following query can show the difference:
select count(ss_sales_price), sum(ss_sales_price), avg(ss_sales_price),
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. 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)
