org.apache.hadoop.hive.ql.exec.vector.ptf

Class VectorPTFEvaluatorAbstractLeadLag

java.lang.Object

org.apache.hadoop.hive.ql.exec.vector.ptf.VectorPTFEvaluatorBase

org.apache.hadoop.hive.ql.exec.vector.ptf.VectorPTFEvaluatorAbstractLeadLag

Direct Known Subclasses:

VectorPTFEvaluatorLag, VectorPTFEvaluatorLead

public abstract class VectorPTFEvaluatorAbstractLeadLag
extends VectorPTFEvaluatorBase

Field Summary

Fields

Modifier and Type	Field and Description
protected int	amt
protected Object	defaultValue
protected int	defaultValueColumn
protected ColumnVector.Type	type

Fields inherited from class org.apache.hadoop.hive.ql.exec.vector.ptf.VectorPTFEvaluatorBase

inputColumnNum, LOG, outputColumnNum

Constructor Summary

Constructors

Constructor and Description
VectorPTFEvaluatorAbstractLeadLag(WindowFrameDef windowFrameDef, VectorExpression inputVecExpr, int outputColumnNum, ColumnVector.Type type, int amt, VectorExpression defaultValueExpression)

Method Summary

Modifier and Type	Method and Description
boolean	canRunOptimizedCalculation(int rowNum, Range range) Whether the evaluator can calculate the result for a given range.
void	evaluateGroupBatch(VectorizedRowBatch batch)
protected Object	getDefaultValue(int rowNum, VectorPTFGroupBatches batches)
ColumnVector.Type	getResultColumnVectorType()
boolean	isCacheableForRange() Whether the results calculated by this evaluator are eligible for caching by PTFValueCache.
void	mapCustomColumns(int[] bufferedColumnMap) VectorPTFGroupBatches class works on a subset of columns, which are mapped by an array of changed indices.
void	resetEvaluator()
boolean	streamsResult()

Methods inherited from class org.apache.hadoop.hive.ql.exec.vector.ptf.VectorPTFEvaluatorBase

doLastBatchWork, evaluateInputExpr, getGroupResult, getNullsLast, getOutputColumnNum, isGroupResultNull, onPartitionEnd, onResultCalculated, runOnRange, setNullsLast

Methods inherited from class java.lang.Object

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

Field Detail

amt

protected int amt

defaultValue

protected Object defaultValue

defaultValueColumn

protected int defaultValueColumn

type

protected ColumnVector.Type type

Constructor Detail

VectorPTFEvaluatorAbstractLeadLag

public VectorPTFEvaluatorAbstractLeadLag(WindowFrameDef windowFrameDef,
                                         VectorExpression inputVecExpr,
                                         int outputColumnNum,
                                         ColumnVector.Type type,
                                         int amt,
                                         VectorExpression defaultValueExpression)

Method Detail

canRunOptimizedCalculation

public boolean canRunOptimizedCalculation(int rowNum,
                                          Range range)

Description copied from class: VectorPTFEvaluatorBase

Whether the evaluator can calculate the result for a given range. The optimization is supposed to save CPU/IO cost in case of evaluators that can provide the result without iterating through the batches of a range. This method is called before every single calculation, so it lets the evaluator store state whether it's able to run an optimized calculation in a given point of time.

Overrides:

canRunOptimizedCalculation in class VectorPTFEvaluatorBase

getDefaultValue

protected Object getDefaultValue(int rowNum,
                                 VectorPTFGroupBatches batches)
                          throws HiveException

Throws:

HiveException

evaluateGroupBatch

public void evaluateGroupBatch(VectorizedRowBatch batch)
                        throws HiveException

Specified by:

evaluateGroupBatch in class VectorPTFEvaluatorBase

Throws:

HiveException

streamsResult

public boolean streamsResult()

Specified by:

streamsResult in class VectorPTFEvaluatorBase

getResultColumnVectorType

public ColumnVector.Type getResultColumnVectorType()

Specified by:

getResultColumnVectorType in class VectorPTFEvaluatorBase

resetEvaluator

public void resetEvaluator()

Specified by:

resetEvaluator in class VectorPTFEvaluatorBase

isCacheableForRange

public boolean isCacheableForRange()

Description copied from class: VectorPTFEvaluatorBase

Whether the results calculated by this evaluator are eligible for caching by PTFValueCache. A result of an evaluator is cacheable, if it returns the same value for the same range within the a PTF partition, regardless of which row the current result is calculated for. That's typically true for most of the evaluators (e.g. sum), but not true for e.g. lead/lag/first_value/last_value, as their results only depend on a relation between the current and some reference row (instead of ranges).

Overrides:

isCacheableForRange in class VectorPTFEvaluatorBase

mapCustomColumns

public void mapCustomColumns(int[] bufferedColumnMap)

Description copied from class: VectorPTFEvaluatorBase

VectorPTFGroupBatches class works on a subset of columns, which are mapped by an array of changed indices. Some evaluators might refer to column indices, so they can adapt to the changed column layout by this call.

Overrides:

mapCustomColumns in class VectorPTFEvaluatorBase