Package org.apache.hadoop.hive.ql.optimizer.stats.annotation

Class Summary

Class	Description
AnnotateStatsProcCtx
AnnotateWithStatistics
StatsRulesProcFactory
StatsRulesProcFactory.DefaultStatsRule	Default rule is to aggregate the statistics from all its parent operators.
StatsRulesProcFactory.FilterStatsRule	FILTER operator does not change the average row size but it does change the number of rows emitted.
StatsRulesProcFactory.GroupByStatsRule	GROUPBY operator changes the number of rows.
StatsRulesProcFactory.JoinStatsRule	JOIN operator can yield any of the following three cases The values of join keys are disjoint in both relations in which case T(RXS) = 0 (we need histograms for this) Join key is primary key on relation R and foreign key on relation S in which case every tuple in S will have a tuple in R T(RXS) = T(S) (we need histograms for this) Both R & S relation have same value for join-key.
StatsRulesProcFactory.LimitStatsRule	LIMIT operator changes the number of rows and thereby the data size.
StatsRulesProcFactory.ReduceSinkStatsRule	ReduceSink operator does not change any of the statistics.
StatsRulesProcFactory.SelectStatsRule	SELECT operator doesn't change the number of rows emitted from the parent operator.
StatsRulesProcFactory.TableScanStatsRule	Collect basic statistics like number of rows, data size and column level statistics from the table.