DRILL-4521: Map variance() and stddev() to var_samp() and stddev_samp() respectiv…

Open minji-kim opened this issue 9 years ago • 1 comments

…ely, and allow for DrillReduceAggregateRule to apply to them

Right now, variance() and stddev() is not mapped to var_samp() and stddev_samp() respectively, and they cannot be reduced to sums of squares (by DrillReduceAggregateRule). DrillReduceAggregateRule allows variance/stddev functions to be aggregated over 2-phase aggregation. Without this, stddev/variance is always done in a single phase aggregation. Added test cases to verify.

Mar 22 '16 00:03 minji-kim

Mar 30 '16 22:03 StevenMPhillips