Package io.prestosql.operator

Class MergeHashSort

java.lang.Object

io.prestosql.operator.MergeHashSort

All Implemented Interfaces:

Closeable, AutoCloseable

public class MergeHashSort
extends Object
implements Closeable

This class performs merge of previously hash sorted pages streams.

Positions are compared using their hash value. It is possible that two distinct values to have same hash value, thus returned stream of Pages can have interleaved positions with same hash value.

Constructor Summary

Constructors

Constructor	Description
MergeHashSort(AggregatedMemoryContext memoryContext, BlockTypeOperators blockTypeOperators)

Method Summary

Modifier and Type	Method	Description
void	close()
WorkProcessor<Page>	merge(List<Type> keyTypes, List<Type> allTypes, List<WorkProcessor<Page>> channels, DriverYieldSignal driverYieldSignal)	Rows with same hash value are guaranteed to be in the same result page.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MergeHashSort

public MergeHashSort(AggregatedMemoryContext memoryContext,
                     BlockTypeOperators blockTypeOperators)

Method Detail

merge

public WorkProcessor<Page> merge(List<Type> keyTypes,
                                 List<Type> allTypes,
                                 List<WorkProcessor<Page>> channels,
                                 DriverYieldSignal driverYieldSignal)

Rows with same hash value are guaranteed to be in the same result page.

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable