Package | Description |
---|---|
org.apache.hadoop.hive.ql.optimizer.stats.annotation |
Modifier and Type | Class and Description |
---|---|
static class |
StatsRulesProcFactory.FilterStatsRule
FILTER operator does not change the average row size but it does change the number of rows
emitted.
|
static class |
StatsRulesProcFactory.GroupByStatsRule
GROUPBY operator changes the number of rows.
|
static class |
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.
|
static class |
StatsRulesProcFactory.LimitStatsRule
LIMIT operator changes the number of rows and thereby the data size.
|
static class |
StatsRulesProcFactory.ReduceSinkStatsRule
ReduceSink operator does not change any of the statistics.
|
static class |
StatsRulesProcFactory.SelectStatsRule
SELECT operator doesn't change the number of rows emitted from the parent operator.
|
static class |
StatsRulesProcFactory.TableScanStatsRule
Collect basic statistics like number of rows, data size and column level statistics from the
table.
|
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