[SPARK-7469] [SQL] DAG visualization: show SQL query operators

The DAG visualization currently displays only low-level Spark primitives (e.g. `map`, `reduceByKey`, `filter` etc.). For SQL, these aren't particularly useful. Instead, we should display higher level physical operators (e.g. `Filter`, `Exchange`, `ShuffleHashJoin`). cc marmbrus

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**Before**
<img src="https://issues.apache.org/jira/secure/attachment/12731586/before.png" width="600px"/>
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**After** (Pay attention to the words)
<img src="https://issues.apache.org/jira/secure/attachment/12731587/after.png" width="600px"/>
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Author: Andrew Or <andrew@databricks.com>

Closes #5999 from andrewor14/dag-viz-sql and squashes the following commits:

0db23a4 [Andrew Or] Merge branch 'master' of github.com:apache/spark into dag-viz-sql
1e211db [Andrew Or] Update comment
0d49fd6 [Andrew Or] Merge branch 'master' of github.com:apache/spark into dag-viz-sql
ffd237a [Andrew Or] Fix style
202dac1 [Andrew Or] Make ignoreParent false by default
e61b1ab [Andrew Or] Visualize SQL operators, not low-level Spark primitives
569034a [Andrew Or] Add a flag to ignore parent settings and scopes

core/src/main/scala/org/apache/spark/rdd/RDDOperationScope.scala

@@ -102,25 +102,33 @@ private[spark] object RDDOperationScope {
   /**
    * Execute the given body such that all RDDs created in this body will have the same scope.
    *
-   * If nesting is allowed, this concatenates the previous scope with the new one in a way that
-   * signifies the hierarchy. Otherwise, if nesting is not allowed, then any children calls to
-   * this method executed in the body will have no effect.
+   * If nesting is allowed, any subsequent calls to this method in the given body will instantiate
+   * child scopes that are nested within our scope. Otherwise, these calls will take no effect.
+   *
+   * Additionally, the caller of this method may optionally ignore the configurations and scopes
+   * set by the higher level caller. In this case, this method will ignore the parent caller's
+   * intention to disallow nesting, and the new scope instantiated will not have a parent. This
+   * is useful for scoping physical operations in Spark SQL, for instance.
    *
    * Note: Return statements are NOT allowed in body.
    */
   private[spark] def withScope[T](
       sc: SparkContext,
       name: String,
-      allowNesting: Boolean)(body: => T): T = {
+      allowNesting: Boolean,
+      ignoreParent: Boolean = false)(body: => T): T = {
     // Save the old scope to restore it later
     val scopeKey = SparkContext.RDD_SCOPE_KEY
     val noOverrideKey = SparkContext.RDD_SCOPE_NO_OVERRIDE_KEY
     val oldScopeJson = sc.getLocalProperty(scopeKey)
     val oldScope = Option(oldScopeJson).map(RDDOperationScope.fromJson)
     val oldNoOverride = sc.getLocalProperty(noOverrideKey)
     try {
-      // Set the scope only if the higher level caller allows us to do so
-      if (sc.getLocalProperty(noOverrideKey) == null) {
+      if (ignoreParent) {
+        // Ignore all parent settings and scopes and start afresh with our own root scope
+        sc.setLocalProperty(scopeKey, new RDDOperationScope(name).toJson)
+      } else if (sc.getLocalProperty(noOverrideKey) == null) {
+        // Otherwise, set the scope only if the higher level caller allows us to do so
         sc.setLocalProperty(scopeKey, new RDDOperationScope(name, oldScope).toJson)
       }
       // Optionally disallow the child body to override our scope

sql/core/src/main/scala/org/apache/spark/sql/columnar/InMemoryColumnarTableScan.scala

@@ -267,7 +267,7 @@ private[sql] case class InMemoryColumnarTableScan(
 
   private val inMemoryPartitionPruningEnabled = sqlContext.conf.inMemoryPartitionPruning
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     if (enableAccumulators) {
       readPartitions.setValue(0)
       readBatches.setValue(0)

sql/core/src/main/scala/org/apache/spark/sql/execution/Aggregate.scala

@@ -121,7 +121,7 @@ case class Aggregate(
     }
   }
 
-  override def execute(): RDD[Row] = attachTree(this, "execute") {
+  protected override def doExecute(): RDD[Row] = attachTree(this, "execute") {
     if (groupingExpressions.isEmpty) {
       child.execute().mapPartitions { iter =>
         val buffer = newAggregateBuffer()

sql/core/src/main/scala/org/apache/spark/sql/execution/Exchange.scala

@@ -109,7 +109,7 @@ case class Exchange(
     serializer
   }
 
-  override def execute(): RDD[Row] = attachTree(this , "execute") {
+  protected override def doExecute(): RDD[Row] = attachTree(this , "execute") {
     newPartitioning match {
       case HashPartitioning(expressions, numPartitions) =>
         // TODO: Eliminate redundant expressions in grouping key and value.

sql/core/src/main/scala/org/apache/spark/sql/execution/ExistingRDD.scala

@@ -106,7 +106,7 @@ private[sql] case class LogicalRDD(output: Seq[Attribute], rdd: RDD[Row])(sqlCon
 
 /** Physical plan node for scanning data from an RDD. */
 private[sql] case class PhysicalRDD(output: Seq[Attribute], rdd: RDD[Row]) extends LeafNode {
-  override def execute(): RDD[Row] = rdd
+  protected override def doExecute(): RDD[Row] = rdd
 }
 
 /** Logical plan node for scanning data from a local collection. */

sql/core/src/main/scala/org/apache/spark/sql/execution/Expand.scala

@@ -43,7 +43,7 @@ case class Expand(
   // as UNKNOWN partitioning
   override def outputPartitioning: Partitioning = UnknownPartitioning(0)
 
-  override def execute(): RDD[Row] = attachTree(this, "execute") {
+  protected override def doExecute(): RDD[Row] = attachTree(this, "execute") {
     child.execute().mapPartitions { iter =>
       // TODO Move out projection objects creation and transfer to
       // workers via closure. However we can't assume the Projection

sql/core/src/main/scala/org/apache/spark/sql/execution/Generate.scala

@@ -46,7 +46,7 @@ case class Generate(
 
   val boundGenerator = BindReferences.bindReference(generator, child.output)
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     if (join) {
       child.execute().mapPartitions { iter =>
         val nullValues = Seq.fill(generator.elementTypes.size)(Literal(null))

sql/core/src/main/scala/org/apache/spark/sql/execution/GeneratedAggregate.scala

@@ -66,7 +66,7 @@ case class GeneratedAggregate(
 
   override def output: Seq[Attribute] = aggregateExpressions.map(_.toAttribute)
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val aggregatesToCompute = aggregateExpressions.flatMap { a =>
       a.collect { case agg: AggregateExpression => agg}
     }

sql/core/src/main/scala/org/apache/spark/sql/execution/LocalTableScan.scala

@@ -30,7 +30,7 @@ private[sql] case class LocalTableScan(output: Seq[Attribute], rows: Seq[Row]) e
 
   private lazy val rdd = sqlContext.sparkContext.parallelize(rows)
 
-  override def execute(): RDD[Row] = rdd
+  protected override def doExecute(): RDD[Row] = rdd
 
 
   override def executeCollect(): Array[Row] = {

sql/core/src/main/scala/org/apache/spark/sql/execution/SparkPlan.scala

@@ -19,7 +19,7 @@ package org.apache.spark.sql.execution
 
 import org.apache.spark.annotation.DeveloperApi
 import org.apache.spark.Logging
-import org.apache.spark.rdd.RDD
+import org.apache.spark.rdd.{RDD, RDDOperationScope}
 import org.apache.spark.sql.SQLContext
 import org.apache.spark.sql.catalyst.{CatalystTypeConverters, trees}
 import org.apache.spark.sql.catalyst.expressions._
@@ -79,14 +79,25 @@ abstract class SparkPlan extends QueryPlan[SparkPlan] with Logging with Serializ
   def requiredChildOrdering: Seq[Seq[SortOrder]] = Seq.fill(children.size)(Nil)
 
   /**
-   * Runs this query returning the result as an RDD.
+   * Returns the result of this query as an RDD[Row] by delegating to doExecute
+   * after adding query plan information to created RDDs for visualization.
+   * Concrete implementations of SparkPlan should override doExecute instead.
    */
-  def execute(): RDD[Row]
+  final def execute(): RDD[Row] = {
+    RDDOperationScope.withScope(sparkContext, nodeName, false, true) {
+      doExecute()
+    }
+  }
 
   /**
-   * Runs this query returning the result as an array.
+   * Overridden by concrete implementations of SparkPlan.
+   * Produces the result of the query as an RDD[Row]
    */
+  protected def doExecute(): RDD[Row]
 
+  /**
+   * Runs this query returning the result as an array.
+   */
   def executeCollect(): Array[Row] = {
     execute().mapPartitions { iter =>
       val converter = CatalystTypeConverters.createToScalaConverter(schema)

sql/core/src/main/scala/org/apache/spark/sql/execution/Window.scala

@@ -112,7 +112,7 @@ case class Window(
     }
   }
 
-  def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     child.execute().mapPartitions { iter =>
       new Iterator[Row] {
 

sql/core/src/main/scala/org/apache/spark/sql/execution/basicOperators.scala

@@ -37,7 +37,7 @@ case class Project(projectList: Seq[NamedExpression], child: SparkPlan) extends
 
   @transient lazy val buildProjection = newMutableProjection(projectList, child.output)
 
-  override def execute(): RDD[Row] = child.execute().mapPartitions { iter =>
+  protected override def doExecute(): RDD[Row] = child.execute().mapPartitions { iter =>
     val resuableProjection = buildProjection()
     iter.map(resuableProjection)
   }
@@ -54,7 +54,7 @@ case class Filter(condition: Expression, child: SparkPlan) extends UnaryNode {
 
   @transient lazy val conditionEvaluator: (Row) => Boolean = newPredicate(condition, child.output)
 
-  override def execute(): RDD[Row] = child.execute().mapPartitions { iter =>
+  protected override def doExecute(): RDD[Row] = child.execute().mapPartitions { iter =>
     iter.filter(conditionEvaluator)
   }
 
@@ -83,7 +83,7 @@ case class Sample(
   override def output: Seq[Attribute] = child.output
 
   // TODO: How to pick seed?
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     if (withReplacement) {
       child.execute().map(_.copy()).sample(withReplacement, upperBound - lowerBound, seed)
     } else {
@@ -99,7 +99,7 @@ case class Sample(
 case class Union(children: Seq[SparkPlan]) extends SparkPlan {
   // TODO: attributes output by union should be distinct for nullability purposes
   override def output: Seq[Attribute] = children.head.output
-  override def execute(): RDD[Row] = sparkContext.union(children.map(_.execute()))
+  protected override def doExecute(): RDD[Row] = sparkContext.union(children.map(_.execute()))
 }
 
 /**
@@ -124,7 +124,7 @@ case class Limit(limit: Int, child: SparkPlan)
 
   override def executeCollect(): Array[Row] = child.executeTake(limit)
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val rdd: RDD[_ <: Product2[Boolean, Row]] = if (sortBasedShuffleOn) {
       child.execute().mapPartitions { iter =>
         iter.take(limit).map(row => (false, row.copy()))
@@ -166,7 +166,7 @@ case class TakeOrdered(limit: Int, sortOrder: Seq[SortOrder], child: SparkPlan)
 
   // TODO: Terminal split should be implemented differently from non-terminal split.
   // TODO: Pick num splits based on |limit|.
-  override def execute(): RDD[Row] = sparkContext.makeRDD(collectData(), 1)
+  protected override def doExecute(): RDD[Row] = sparkContext.makeRDD(collectData(), 1)
 
   override def outputOrdering: Seq[SortOrder] = sortOrder
 }
@@ -186,7 +186,7 @@ case class Sort(
   override def requiredChildDistribution: Seq[Distribution] =
     if (global) OrderedDistribution(sortOrder) :: Nil else UnspecifiedDistribution :: Nil
 
-  override def execute(): RDD[Row] = attachTree(this, "sort") {
+  protected override def doExecute(): RDD[Row] = attachTree(this, "sort") {
     child.execute().mapPartitions( { iterator =>
       val ordering = newOrdering(sortOrder, child.output)
       iterator.map(_.copy()).toArray.sorted(ordering).iterator
@@ -214,7 +214,7 @@ case class ExternalSort(
   override def requiredChildDistribution: Seq[Distribution] =
     if (global) OrderedDistribution(sortOrder) :: Nil else UnspecifiedDistribution :: Nil
 
-  override def execute(): RDD[Row] = attachTree(this, "sort") {
+  protected override def doExecute(): RDD[Row] = attachTree(this, "sort") {
     child.execute().mapPartitions( { iterator =>
       val ordering = newOrdering(sortOrder, child.output)
       val sorter = new ExternalSorter[Row, Null, Row](ordering = Some(ordering))
@@ -244,7 +244,7 @@ case class Distinct(partial: Boolean, child: SparkPlan) extends UnaryNode {
   override def requiredChildDistribution: Seq[Distribution] =
     if (partial) UnspecifiedDistribution :: Nil else ClusteredDistribution(child.output) :: Nil
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     child.execute().mapPartitions { iter =>
       val hashSet = new scala.collection.mutable.HashSet[Row]()
 
@@ -270,7 +270,7 @@ case class Repartition(numPartitions: Int, shuffle: Boolean, child: SparkPlan)
   extends UnaryNode {
   override def output: Seq[Attribute] = child.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     child.execute().map(_.copy()).coalesce(numPartitions, shuffle)
   }
 }
@@ -285,7 +285,7 @@ case class Repartition(numPartitions: Int, shuffle: Boolean, child: SparkPlan)
 case class Except(left: SparkPlan, right: SparkPlan) extends BinaryNode {
   override def output: Seq[Attribute] = left.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     left.execute().map(_.copy()).subtract(right.execute().map(_.copy()))
   }
 }
@@ -299,7 +299,7 @@ case class Except(left: SparkPlan, right: SparkPlan) extends BinaryNode {
 case class Intersect(left: SparkPlan, right: SparkPlan) extends BinaryNode {
   override def output: Seq[Attribute] = children.head.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     left.execute().map(_.copy()).intersection(right.execute().map(_.copy()))
   }
 }
@@ -314,5 +314,5 @@ case class Intersect(left: SparkPlan, right: SparkPlan) extends BinaryNode {
 case class OutputFaker(output: Seq[Attribute], child: SparkPlan) extends SparkPlan {
   def children: Seq[SparkPlan] = child :: Nil
 
-  def execute(): RDD[Row] = child.execute()
+  protected override def doExecute(): RDD[Row] = child.execute()
 }

sql/core/src/main/scala/org/apache/spark/sql/execution/commands.scala

@@ -64,7 +64,7 @@ private[sql] case class ExecutedCommand(cmd: RunnableCommand) extends SparkPlan
 
   override def executeTake(limit: Int): Array[Row] = sideEffectResult.take(limit).toArray
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val converted = sideEffectResult.map(r =>
       CatalystTypeConverters.convertToCatalyst(r, schema).asInstanceOf[Row])
     sqlContext.sparkContext.parallelize(converted, 1)

sql/core/src/main/scala/org/apache/spark/sql/execution/debug/package.scala

@@ -125,7 +125,7 @@ package object debug {
       }
     }
 
-    def execute(): RDD[Row] = {
+    protected override def doExecute(): RDD[Row] = {
       child.execute().mapPartitions { iter =>
         new Iterator[Row] {
           def hasNext: Boolean = iter.hasNext
@@ -193,7 +193,7 @@ package object debug {
 
     def children: List[SparkPlan] = child :: Nil
 
-    def execute(): RDD[Row] = {
+    protected override def doExecute(): RDD[Row] = {
       child.execute().map { row =>
         try typeCheck(row, child.schema) catch {
           case e: Exception =>

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastHashJoin.scala

@@ -66,7 +66,7 @@ case class BroadcastHashJoin(
     sparkContext.broadcast(hashed)
   }
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val broadcastRelation = Await.result(broadcastFuture, timeout)
 
     streamedPlan.execute().mapPartitions { streamedIter =>

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastLeftSemiJoinHash.scala

@@ -38,7 +38,7 @@ case class BroadcastLeftSemiJoinHash(
 
   override def output: Seq[Attribute] = left.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val buildIter= buildPlan.execute().map(_.copy()).collect().toIterator
     val hashSet = new java.util.HashSet[Row]()
     var currentRow: Row = null

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoin.scala

@@ -61,7 +61,7 @@ case class BroadcastNestedLoopJoin(
   @transient private lazy val boundCondition =
     newPredicate(condition.getOrElse(Literal(true)), left.output ++ right.output)
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val broadcastedRelation =
       sparkContext.broadcast(broadcast.execute().map(_.copy()).collect().toIndexedSeq)
 

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/CartesianProduct.scala

@@ -30,7 +30,7 @@ import org.apache.spark.sql.execution.{BinaryNode, SparkPlan}
 case class CartesianProduct(left: SparkPlan, right: SparkPlan) extends BinaryNode {
   override def output: Seq[Attribute] = left.output ++ right.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val leftResults = left.execute().map(_.copy())
     val rightResults = right.execute().map(_.copy())
 

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/HashOuterJoin.scala

@@ -183,7 +183,7 @@ case class HashOuterJoin(
     hashTable
   }
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val joinedRow = new JoinedRow()
     left.execute().zipPartitions(right.execute()) { (leftIter, rightIter) =>
       // TODO this probably can be replaced by external sort (sort merged join?)

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/LeftSemiJoinBNL.scala

@@ -47,7 +47,7 @@ case class LeftSemiJoinBNL(
   @transient private lazy val boundCondition =
     newPredicate(condition.getOrElse(Literal(true)), left.output ++ right.output)
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val broadcastedRelation =
       sparkContext.broadcast(broadcast.execute().map(_.copy()).collect().toIndexedSeq)
 

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/LeftSemiJoinHash.scala

@@ -42,7 +42,7 @@ case class LeftSemiJoinHash(
 
   override def output: Seq[Attribute] = left.output
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     buildPlan.execute().zipPartitions(streamedPlan.execute()) { (buildIter, streamIter) =>
       val hashSet = new java.util.HashSet[Row]()
       var currentRow: Row = null

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ShuffledHashJoin.scala

@@ -43,7 +43,7 @@ case class ShuffledHashJoin(
   override def requiredChildDistribution: Seq[ClusteredDistribution] =
     ClusteredDistribution(leftKeys) :: ClusteredDistribution(rightKeys) :: Nil
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     buildPlan.execute().zipPartitions(streamedPlan.execute()) { (buildIter, streamIter) =>
       val hashed = HashedRelation(buildIter, buildSideKeyGenerator)
       hashJoin(streamIter, hashed)

sql/core/src/main/scala/org/apache/spark/sql/execution/joins/SortMergeJoin.scala

@@ -60,7 +60,7 @@ case class SortMergeJoin(
   private def requiredOrders(keys: Seq[Expression]): Seq[SortOrder] =
     keys.map(SortOrder(_, Ascending))
 
-  override def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val leftResults = left.execute().map(_.copy())
     val rightResults = right.execute().map(_.copy())
 

sql/core/src/main/scala/org/apache/spark/sql/execution/pythonUdfs.scala

@@ -228,7 +228,7 @@ case class BatchPythonEvaluation(udf: PythonUDF, output: Seq[Attribute], child:
 
   def children: Seq[SparkPlan] = child :: Nil
 
-  def execute(): RDD[Row] = {
+  protected override def doExecute(): RDD[Row] = {
     val childResults = child.execute().map(_.copy())
 
     val parent = childResults.mapPartitions { iter =>