org.apache.flink.table.planner.functions.aggfunctions

Class SingleValueAggFunction

java.lang.Object

org.apache.flink.table.functions.UserDefinedFunction

org.apache.flink.table.functions.DeclarativeAggregateFunction

org.apache.flink.table.planner.functions.aggfunctions.SingleValueAggFunction

All Implemented Interfaces:

Serializable, FunctionDefinition

Direct Known Subclasses:

SingleValueAggFunction.BooleanSingleValueAggFunction, SingleValueAggFunction.ByteSingleValueAggFunction, SingleValueAggFunction.CharSingleValueAggFunction, SingleValueAggFunction.DateSingleValueAggFunction, SingleValueAggFunction.DecimalSingleValueAggFunction, SingleValueAggFunction.DoubleSingleValueAggFunction, SingleValueAggFunction.FloatSingleValueAggFunction, SingleValueAggFunction.IntSingleValueAggFunction, SingleValueAggFunction.LongSingleValueAggFunction, SingleValueAggFunction.ShortSingleValueAggFunction, SingleValueAggFunction.StringSingleValueAggFunction, SingleValueAggFunction.TimeSingleValueAggFunction, SingleValueAggFunction.TimestampLtzSingleValueAggFunction, SingleValueAggFunction.TimestampSingleValueAggFunction

public abstract class SingleValueAggFunction
extends DeclarativeAggregateFunction

Base class for built-in single value aggregate function.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SingleValueAggFunction.BooleanSingleValueAggFunction Built-in boolean single value aggregate function.
static class	SingleValueAggFunction.ByteSingleValueAggFunction Built-in byte single value aggregate function.
static class	SingleValueAggFunction.CharSingleValueAggFunction Built-in char single value aggregate function.
static class	SingleValueAggFunction.DateSingleValueAggFunction Built-in date single value aggregate function.
static class	SingleValueAggFunction.DecimalSingleValueAggFunction Built-in decimal single value aggregate function.
static class	SingleValueAggFunction.DoubleSingleValueAggFunction Built-in double single value aggregate function.
static class	SingleValueAggFunction.FloatSingleValueAggFunction Built-in float single value aggregate function.
static class	SingleValueAggFunction.IntSingleValueAggFunction Built-in int single value aggregate function.
static class	SingleValueAggFunction.LongSingleValueAggFunction Built-in long single value aggregate function.
static class	SingleValueAggFunction.ShortSingleValueAggFunction Built-in short single value aggregate function.
static class	SingleValueAggFunction.StringSingleValueAggFunction Built-in string single value aggregate function.
static class	SingleValueAggFunction.TimeSingleValueAggFunction Built-in time single value aggregate function.
static class	SingleValueAggFunction.TimestampLtzSingleValueAggFunction Built-in timestampLtz single value aggregate function.
static class	SingleValueAggFunction.TimestampSingleValueAggFunction Built-in timestamp single value aggregate function.

Constructor Summary

Constructors

Constructor and Description
SingleValueAggFunction()

Method Summary

Modifier and Type	Method and Description
Expression[]	accumulateExpressions() Expressions for accumulating the mutable aggregation buffer based on an input row.
UnresolvedReferenceExpression[]	aggBufferAttributes() All fields of the aggregate buffer.
DataType[]	getAggBufferTypes() All types of the aggregate buffer.
Expression	getValueExpression() An expression which returns the final value for this aggregate function.
Expression[]	initialValuesExpressions() Expressions for initializing empty aggregation buffers.
Expression[]	mergeExpressions() A sequence of expressions for merging two aggregation buffers together.
int	operandCount() How many operands your function will deal with.
Expression[]	retractExpressions() Expressions for retracting the mutable aggregation buffer based on an input row.

Methods inherited from class org.apache.flink.table.functions.DeclarativeAggregateFunction

getKind, getResultType, getTypeInference, mergeOperand, mergeOperands, operand, operands

Methods inherited from class org.apache.flink.table.functions.UserDefinedFunction

close, functionIdentifier, open, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.table.functions.FunctionDefinition

getRequirements, isDeterministic

Constructor Detail

SingleValueAggFunction

public SingleValueAggFunction()

Method Detail

operandCount

public int operandCount()

Description copied from class: DeclarativeAggregateFunction

How many operands your function will deal with.

Specified by:

operandCount in class DeclarativeAggregateFunction

aggBufferAttributes

public UnresolvedReferenceExpression[] aggBufferAttributes()

Description copied from class: DeclarativeAggregateFunction

All fields of the aggregate buffer.

Specified by:

aggBufferAttributes in class DeclarativeAggregateFunction

getAggBufferTypes

public DataType[] getAggBufferTypes()

Description copied from class: DeclarativeAggregateFunction

All types of the aggregate buffer.

Specified by:

getAggBufferTypes in class DeclarativeAggregateFunction

initialValuesExpressions

public Expression[] initialValuesExpressions()

Description copied from class: DeclarativeAggregateFunction

Expressions for initializing empty aggregation buffers.

Specified by:

initialValuesExpressions in class DeclarativeAggregateFunction

accumulateExpressions

public Expression[] accumulateExpressions()

Description copied from class: DeclarativeAggregateFunction

Expressions for accumulating the mutable aggregation buffer based on an input row.

Specified by:

accumulateExpressions in class DeclarativeAggregateFunction

retractExpressions

public Expression[] retractExpressions()

Description copied from class: DeclarativeAggregateFunction

Expressions for retracting the mutable aggregation buffer based on an input row.

Specified by:

retractExpressions in class DeclarativeAggregateFunction

mergeExpressions

public Expression[] mergeExpressions()

Description copied from class: DeclarativeAggregateFunction

A sequence of expressions for merging two aggregation buffers together. When defining these expressions, you can use the syntax attributeName and mergeOperand(attributeName) to refer to the attributes corresponding to each of the buffers being merged.

Specified by:

mergeExpressions in class DeclarativeAggregateFunction

getValueExpression

public Expression getValueExpression()

Description copied from class: DeclarativeAggregateFunction

An expression which returns the final value for this aggregate function.

Specified by:

getValueExpression in class DeclarativeAggregateFunction