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[SPARK-34707][SQL] Code-gen broadcast nested loop join (left outer/right outer) #31931

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[SPARK-34707][SQL] Code-gen broadcast nested loop join (left outer/right outer) #31931

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08e47d2
Left/Right outer broadcast nested loop join codegen
linzebing Mar 22, 2021
8ee7536
handle broadcast side is empty and add a test to cover it
linzebing Mar 23, 2021
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47 changes: 46 additions & 1 deletion ...ore/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoinExec.scala
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Original file line number Diff line number Diff line change
Expand Up @@ -396,7 +396,8 @@ case class BroadcastNestedLoopJoinExec(
}

override def supportCodegen: Boolean = (joinType, buildSide) match {
case (_: InnerLike, _) | (LeftSemi | LeftAnti, BuildRight) => true
case (_: InnerLike, _) | (LeftOuter, BuildRight) | (RightOuter, BuildLeft) |
(LeftSemi | LeftAnti, BuildRight) => true
case _ => false
}

Expand All @@ -413,6 +414,7 @@ case class BroadcastNestedLoopJoinExec(
override def doConsume(ctx: CodegenContext, input: Seq[ExprCode], row: ExprCode): String = {
(joinType, buildSide) match {
case (_: InnerLike, _) => codegenInner(ctx, input)
case (LeftOuter, BuildRight) | (RightOuter, BuildLeft) => codegenOuter(ctx, input)
case (LeftSemi, BuildRight) => codegenLeftExistence(ctx, input, exists = true)
case (LeftAnti, BuildRight) => codegenLeftExistence(ctx, input, exists = false)
case _ =>
Expand Down Expand Up @@ -458,6 +460,49 @@ case class BroadcastNestedLoopJoinExec(
""".stripMargin
}

private def codegenOuter(ctx: CodegenContext, input: Seq[ExprCode]): String = {
val (buildRowArray, buildRowArrayTerm) = prepareBroadcast(ctx)
val (buildRow, checkCondition, _) = getJoinCondition(ctx, input, streamed, broadcast)
val buildVars = genBuildSideVars(ctx, buildRow, broadcast)

val resultVars = buildSide match {
case BuildLeft => buildVars ++ input
case BuildRight => input ++ buildVars
}
val arrayIndex = ctx.freshName("arrayIndex")
val shouldOutputRow = ctx.freshName("shouldOutputRow")
val foundMatch = ctx.freshName("foundMatch")
val numOutput = metricTerm(ctx, "numOutputRows")

if (buildRowArray.isEmpty) {
s"""
|UnsafeRow $buildRow = null;
|$numOutput.add(1);
|${consume(ctx, resultVars)}
""".stripMargin
} else {
s"""
|boolean $foundMatch = false;
|for (int $arrayIndex = 0; $arrayIndex < $buildRowArrayTerm.length; $arrayIndex++) {
| UnsafeRow $buildRow = (UnsafeRow) $buildRowArrayTerm[$arrayIndex];
| boolean $shouldOutputRow = false;
| $checkCondition {
| $shouldOutputRow = true;
| $foundMatch = true;
| }
| if ($arrayIndex == $buildRowArrayTerm.length - 1 && !$foundMatch) {
| $buildRow = null;
| $shouldOutputRow = true;
| }
| if ($shouldOutputRow) {
| $numOutput.add(1);
| ${consume(ctx, resultVars)}
| }
|}
""".stripMargin
}
}

private def codegenLeftExistence(
ctx: CodegenContext,
input: Seq[ExprCode],
Expand Down
47 changes: 47 additions & 0 deletions sql/core/src/test/scala/org/apache/spark/sql/execution/WholeStageCodegenSuite.scala
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Expand Up @@ -211,6 +211,53 @@ class WholeStageCodegenSuite extends QueryTest with SharedSparkSession
}
}

test("Left/Right outer BroadcastNestedLoopJoinExec should be included in WholeStageCodegen") {
val df1 = spark.range(4).select($"id".as("k1"))
val df2 = spark.range(3).select($"id".as("k2"))
val df3 = spark.range(2).select($"id".as("k3"))
val df4 = spark.range(0).select($"id".as("k4"))

Seq(true, false).foreach { codegenEnabled =>
withSQLConf(SQLConf.WHOLESTAGE_CODEGEN_ENABLED.key -> codegenEnabled.toString) {
// test left outer join
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how about adding an extra test case for broadcast side being empty?

val leftOuterJoinDF = df1.join(df2, $"k1" > $"k2", "left_outer")
var hasJoinInCodegen = leftOuterJoinDF.queryExecution.executedPlan.collect {
case WholeStageCodegenExec(_: BroadcastNestedLoopJoinExec) => true
}.size === 1
assert(hasJoinInCodegen == codegenEnabled)
checkAnswer(leftOuterJoinDF,
Seq(Row(0, null), Row(1, 0), Row(2, 0), Row(2, 1), Row(3, 0), Row(3, 1), Row(3, 2)))

// test right outer join
val rightOuterJoinDF = df1.join(df2, $"k1" < $"k2", "right_outer")
hasJoinInCodegen = rightOuterJoinDF.queryExecution.executedPlan.collect {
case WholeStageCodegenExec(_: BroadcastNestedLoopJoinExec) => true
}.size === 1
assert(hasJoinInCodegen == codegenEnabled)
checkAnswer(rightOuterJoinDF, Seq(Row(null, 0), Row(0, 1), Row(0, 2), Row(1, 2)))

// test a combination of left outer and right outer joins
val twoJoinsDF = df1.join(df2, $"k1" > $"k2" + 1, "right_outer")
.join(df3, $"k1" <= $"k3", "left_outer")
hasJoinInCodegen = twoJoinsDF.queryExecution.executedPlan.collect {
case WholeStageCodegenExec(BroadcastNestedLoopJoinExec(
_: BroadcastNestedLoopJoinExec, _, _, _, _)) => true
}.size === 1
assert(hasJoinInCodegen == codegenEnabled)
checkAnswer(twoJoinsDF,
Seq(Row(2, 0, null), Row(3, 0, null), Row(3, 1, null), Row(null, 2, null)))

// test build side is empty
val buildSideIsEmptyDF = df3.join(df4, $"k3" > $"k4", "left_outer")
hasJoinInCodegen = buildSideIsEmptyDF.queryExecution.executedPlan.collect {
case WholeStageCodegenExec(_: BroadcastNestedLoopJoinExec) => true
}.size === 1
assert(hasJoinInCodegen == codegenEnabled)
checkAnswer(buildSideIsEmptyDF, Seq(Row(0, null), Row(1, null)))
}
}
}

test("Left semi/anti BroadcastNestedLoopJoinExec should be included in WholeStageCodegen") {
val df1 = spark.range(4).select($"id".as("k1"))
val df2 = spark.range(3).select($"id".as("k2"))
Expand Down
4 changes: 2 additions & 2 deletions sql/core/src/test/scala/org/apache/spark/sql/execution/joins/OuterJoinSuite.scala
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Expand Up @@ -149,7 +149,7 @@ class OuterJoinSuite extends SparkPlanTest with SharedSparkSession {
}
}

test(s"$testName using BroadcastNestedLoopJoin build left") {
testWithWholeStageCodegenOnAndOff(s"$testName using BroadcastNestedLoopJoin build left") { _ =>
withSQLConf(SQLConf.SHUFFLE_PARTITIONS.key -> "1") {
checkAnswer2(leftRows, rightRows, (left: SparkPlan, right: SparkPlan) =>
BroadcastNestedLoopJoinExec(left, right, BuildLeft, joinType, Some(condition)),
Expand All @@ -158,7 +158,7 @@ class OuterJoinSuite extends SparkPlanTest with SharedSparkSession {
}
}

test(s"$testName using BroadcastNestedLoopJoin build right") {
testWithWholeStageCodegenOnAndOff(s"$testName using BroadcastNestedLoopJoin build right") { _ =>
withSQLConf(SQLConf.SHUFFLE_PARTITIONS.key -> "1") {
checkAnswer2(leftRows, rightRows, (left: SparkPlan, right: SparkPlan) =>
BroadcastNestedLoopJoinExec(left, right, BuildRight, joinType, Some(condition)),
Expand Down
6 changes: 3 additions & 3 deletions sql/core/src/test/scala/org/apache/spark/sql/execution/metric/SQLMetricsSuite.scala
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Expand Up @@ -452,11 +452,11 @@ class SQLMetricsSuite extends SharedSparkSession with SQLMetricsTestUtils
"testData2.a * testDataForJoin.a != testData2.a + testDataForJoin.a"
val rightQuery = "SELECT * FROM testData2 RIGHT JOIN testDataForJoin ON " +
"testData2.a * testDataForJoin.a != testData2.a + testDataForJoin.a"
Seq((leftQuery, false), (rightQuery, false), (leftQuery, true), (rightQuery, true))
.foreach { case (query, enableWholeStage) =>
Seq((leftQuery, 0L, false), (rightQuery, 0L, false), (leftQuery, 1L, true),
(rightQuery, 1L, true)).foreach { case (query, nodeId, enableWholeStage) =>
val df = spark.sql(query)
testSparkPlanMetrics(df, 2, Map(
0L -> (("BroadcastNestedLoopJoin", Map(
nodeId -> (("BroadcastNestedLoopJoin", Map(
"number of output rows" -> 12L)))),
enableWholeStage
)
Expand Down