org.apache.flink.table.codegen.expr.SumAggFunction.scala Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* to you under the Apache License, Version 2.0 (the
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* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
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*/
package org.apache.flink.table.codegen.expr
import org.apache.flink.table.api.scala._
import org.apache.flink.table.dataformat.Decimal
import org.apache.flink.table.expressions._
import org.apache.flink.table.functions.DeclarativeAggregateFunction
import org.apache.flink.table.types.{DataTypes, DecimalType, InternalType}
/**
* built-in sum aggregate function
*/
abstract class SumAggFunction extends DeclarativeAggregateFunction {
override def inputCount: Int = 1
private lazy val sum = UnresolvedAggBufferReference("sum", getResultType)
override def aggBufferAttributes: Seq[UnresolvedAggBufferReference] = Seq(sum)
override def initialValuesExpressions: Seq[Expression] = Seq(
/* sum = */ Null(sum.resultType)
)
override def accumulateExpressions: Seq[Expression] = Seq(
/* sum = */ IsNull(operands(0)) ? (sum, IsNull(sum) ? (operands(0), sum + operands(0)))
)
override def mergeExpressions: Seq[Expression] = Seq(
If(IsNull(sum.right), sum.left,
If(IsNull(sum.left), sum.right, sum.left + sum.right))
)
override def getValueExpression: Expression = sum
}
/**
* Built-in Int Sum aggregate function
*/
class IntSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.INT
}
/**
* Built-in Byte Sum aggregate function
*/
class ByteSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.BYTE
}
/**
* Built-in Short Sum aggregate function
*/
class ShortSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.SHORT
}
/**
* Built-in Long Sum aggregate function
*/
class LongSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.LONG
}
/**
* Built-in Float Sum aggregate function
*/
class FloatSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.FLOAT
}
/**
* Built-in Double Sum aggregate function
*/
class DoubleSumAggFunction extends SumAggFunction {
override def getResultType: InternalType = DataTypes.DOUBLE
}
/**
* Built-in Decimal Sum aggregate function
*/
class DecimalSumAggFunction(argType: DecimalType)
extends SumAggFunction {
override def getResultType: InternalType =
Decimal.inferAggSumType(argType.precision, argType.scale)
}