org.apache.flink.table.planner.plan.rules.physical.batch.RemoveRedundantLocalRankRule.scala Maven / Gradle / Ivy

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 * distributed with this work for additional information
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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.flink.table.planner.plan.rules.physical.batch

import org.apache.flink.table.planner.plan.nodes.FlinkConventions
import org.apache.flink.table.planner.plan.nodes.physical.batch.BatchPhysicalRank

import org.apache.calcite.plan.RelOptRule._
import org.apache.calcite.plan.{RelOptRule, RelOptRuleCall}
import org.apache.calcite.rel.RelNode

import scala.collection.JavaConversions._

/**
  * Planner rule that matches a global [[BatchPhysicalRank]] on a local [[BatchPhysicalRank]],
  * and merge them into a global [[BatchPhysicalRank]].
  */
class RemoveRedundantLocalRankRule extends RelOptRule(
  operand(classOf[BatchPhysicalRank],
    operand(classOf[BatchPhysicalRank],
      operand(classOf[RelNode], FlinkConventions.BATCH_PHYSICAL, any))),
  "RemoveRedundantLocalRankRule") {

  override def matches(call: RelOptRuleCall): Boolean = {
    val globalRank: BatchPhysicalRank = call.rel(0)
    val localRank: BatchPhysicalRank = call.rel(1)
    globalRank.isGlobal && !localRank.isGlobal &&
      globalRank.rankType == localRank.rankType &&
      globalRank.partitionKey == localRank.partitionKey &&
      globalRank.orderKey == globalRank.orderKey &&
      globalRank.rankEnd == localRank.rankEnd
  }

  override def onMatch(call: RelOptRuleCall): Unit = {
    val globalRank: BatchPhysicalRank = call.rel(0)
    val inputOfLocalRank: RelNode = call.rel(2)
    val newGlobalRank = globalRank.copy(globalRank.getTraitSet, List(inputOfLocalRank))
    call.transformTo(newGlobalRank)
  }
}

object RemoveRedundantLocalRankRule {
  val INSTANCE: RelOptRule = new RemoveRedundantLocalRankRule
}