org.apache.flink.table.planner.plan.rules.logical.StreamLogicalWindowAggregateRule.scala Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.flink.table.planner.plan.rules.logical
import org.apache.flink.table.api.{TableException, ValidationException}
import org.apache.flink.table.expressions.FieldReferenceExpression
import org.apache.flink.table.planner.calcite.FlinkTypeFactory
import org.apache.flink.table.planner.calcite.FlinkTypeFactory.toLogicalType
import org.apache.flink.table.runtime.types.LogicalTypeDataTypeConverter.fromLogicalTypeToDataType
import org.apache.calcite.rel.`type`.RelDataType
import org.apache.calcite.rel.logical.{LogicalAggregate, LogicalProject}
import org.apache.calcite.rex._
import org.apache.calcite.sql.`type`.{SqlTypeFamily, SqlTypeName}
import _root_.java.math.{BigDecimal => JBigDecimal}
/**
* Planner rule that transforms simple [[LogicalAggregate]] on a [[LogicalProject]]
* with windowing expression to
* [[org.apache.flink.table.planner.plan.nodes.calcite.LogicalWindowAggregate]]
* for stream.
*/
class StreamLogicalWindowAggregateRule
extends LogicalWindowAggregateRuleBase("StreamLogicalWindowAggregateRule") {
/** Returns a reference to the time attribute with a time indicator type */
override private[table] def getInAggregateGroupExpression(
rexBuilder: RexBuilder,
windowExpression: RexCall): RexNode = {
val timeAttribute = windowExpression.operands.get(0)
if (!FlinkTypeFactory.isTimeIndicatorType(timeAttribute.getType)) {
throw new TableException(s"Window aggregate can only be defined over a " +
s"time attribute column, but ${timeAttribute.getType} encountered.")
}
timeAttribute
}
/** Returns a zero literal of a timestamp type */
override private[table] def getOutAggregateGroupExpression(
rexBuilder: RexBuilder,
windowExpression: RexCall): RexNode = {
// Create a literal with normal SqlTypeName.TIMESTAMP
// in case we reference a rowtime field.
rexBuilder.makeZeroLiteral(windowExpression.getType)
}
private[table] override def getTimeFieldReference(
operand: RexNode,
timeAttributeIndex: Int,
rowType: RelDataType): FieldReferenceExpression = {
if (!FlinkTypeFactory.isTimeIndicatorType(operand.getType)) {
throw new ValidationException("Window can only be defined over a time attribute column.")
}
val fieldName = rowType.getFieldList.get(timeAttributeIndex).getName
val fieldType = rowType.getFieldList.get(timeAttributeIndex).getType
new FieldReferenceExpression(
fieldName,
fromLogicalTypeToDataType(toLogicalType(fieldType)),
0,
timeAttributeIndex)
}
def getOperandAsLong(call: RexCall, idx: Int): Long =
call.getOperands.get(idx) match {
case v: RexLiteral if v.getTypeName.getFamily == SqlTypeFamily.INTERVAL_DAY_TIME =>
v.getValue.asInstanceOf[JBigDecimal].longValue()
case _: RexLiteral => throw new TableException(
"Window aggregate only support SECOND, MINUTE, HOUR, DAY as the time unit. " +
"MONTH and YEAR time unit are not supported yet.")
case _ => throw new TableException("Only constant window descriptors are supported.")
}
}
object StreamLogicalWindowAggregateRule {
val INSTANCE = new StreamLogicalWindowAggregateRule
}