org.apache.spark.sql.columnar

Interface ColumnStats

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

BinaryColumnStats, BooleanColumnStats, ByteColumnStats, DateColumnStats, DoubleColumnStats, FloatColumnStats, GenericColumnStats, IntColumnStats, LongColumnStats, NoopColumnStats, ShortColumnStats, StringColumnStats, TimestampColumnStats

public interface ColumnStats
extends scala.Serializable

Used to collect statistical information when building in-memory columns.

NOTE: we intentionally avoid using Ordering[T] to compare values here because Ordering[T] brings significant performance penalty.

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.spark.sql.catalyst.expressions.Row	collectedStatistics() Column statistics represented as a single row, currently including closed lower bound, closed upper bound and null count.
int	count()
void	gatherStats(org.apache.spark.sql.catalyst.expressions.Row row, int ordinal) Gathers statistics information from row(ordinal).
int	nullCount()
long	sizeInBytes()

Method Detail

count

int count()

nullCount

int nullCount()

sizeInBytes

long sizeInBytes()

gatherStats

void gatherStats(org.apache.spark.sql.catalyst.expressions.Row row,
               int ordinal)

Gathers statistics information from row(ordinal).

collectedStatistics

org.apache.spark.sql.catalyst.expressions.Row collectedStatistics()

Column statistics represented as a single row, currently including closed lower bound, closed upper bound and null count.