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
Row	collectedStatistics() Column statistics represented as a single row, currently including closed lower bound, closed upper bound and null count.
int	count()
void	gatherStats(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(Row row,
               int ordinal)

Gathers statistics information from row(ordinal).

collectedStatistics

Row collectedStatistics()

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