Scala Sort类代码示例

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本文整理汇总了Scala中org.apache.spark.sql.catalyst.plans.logical.Sort类的典型用法代码示例。如果您正苦于以下问题：Scala Sort类的具体用法？Scala Sort怎么用？Scala Sort使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。

在下文中一共展示了Sort类的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于我们的系统推荐出更棒的Scala代码示例。

示例1: NaiveOrderResolution

//设置package包名称以及导入依赖的类
package by.skaryna.rules

import org.apache.spark.sql.catalyst.expressions.{Alias, AttributeReference, Expression, NamedExpression, SortOrder}
import org.apache.spark.sql.catalyst.plans.logical.{LogicalPlan, Project, Sort}
import org.apache.spark.sql.catalyst.rules.Rule


object NaiveOrderResolution extends Rule[LogicalPlan] {
  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
    case Sort(Seq(order1), global1, Project(projectList, Sort(Seq(order2), global2, child2)))
      if global1 == global2 && order1.direction == order2.direction &&
        isOrderColumnRenamed(projectList, order1.child, order2.child) =>

      val prunedProject = Project(projectList, child2)
      Sort(Seq(order1), global1, prunedProject)
  }

  private[skaryna] def isOrderColumnRenamed(projectList: Seq[NamedExpression],
                                            orderExpr1: Expression, orderExpr2: Expression): Boolean = {
    val aliasMatch = projectList.collect {
      case alias: Alias =>
        alias.child == orderExpr2 && orderExpr1.isInstanceOf[AttributeReference] &&
          alias.exprId == orderExpr1.asInstanceOf[AttributeReference].exprId
    }
    aliasMatch.contains(true)
  }
}

开发者ID:yuribogomolov，项目名称:skaryna，代码行数:28，代码来源:NaiveOrderResolution.scala

示例2: NaiveOrderResolutionTest

//设置package包名称以及导入依赖的类
package by.skaryna.rules

import org.apache.spark.sql.catalyst.plans.logical.{LogicalPlan, Project, Sort}
import org.apache.spark.sql.{DataFrame, SparkSession}
import org.apache.spark.sql.functions._
import org.apache.spark.sql.types.LongType
import org.scalatest.{BeforeAndAfter, FlatSpec}


class NaiveOrderResolutionTest extends FlatSpec with BeforeAndAfter  {
  private var spark: SparkSession = _

  before {
    spark = SparkSession.builder.
      master("local[*]")
      .withExtensions(extensions => extensions.injectOptimizerRule(session => NaiveOrderResolution))
      .config("spark.ui.enabled", "false")
      .getOrCreate()
  }

  after {
    if (spark != null) {
      spark.stop()
    }
  }

  "NaiveOrderResolution" should "avoid unnecessary sorting" in {
    val df = generateDataFrame(10)
    val sorted = df.sort("key")
    val renamed = sorted.withColumnRenamed("key", "key2")
    val sortedAgain = renamed.sort("key2")
    assert(checkOptimizedPlan(sortedAgain.queryExecution.optimizedPlan))
  }

  private def checkOptimizedPlan(logicalPlan: LogicalPlan): Boolean = logicalPlan match {
    case Sort(_, _, Project(_, Project(_, _))) => true
    case _ => false
  }

  private def generateDataFrame(cnt: Int): DataFrame = {
    val ids = spark.sqlContext.range(0, cnt)
    ids.withColumn("key", (rand() * 1000000).cast(LongType))
  }
}

开发者ID:yuribogomolov，项目名称:skaryna，代码行数:45，代码来源:NaiveOrderResolutionTest.scala

注：本文中的org.apache.spark.sql.catalyst.plans.logical.Sort类示例整理自Github/MSDocs等源码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。