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author | Wenchen Fan <wenchen@databricks.com> | 2015-11-18 10:23:12 -0800 |
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committer | Michael Armbrust <michael@databricks.com> | 2015-11-18 10:23:12 -0800 |
commit | 33b837333435ceb0c04d1f361a5383c4fe6a5a75 (patch) | |
tree | 04a87253d495d31efbc2565a49cbb48c2ac7053d /sql | |
parent | cffb899c4397ecccedbcc41e7cf3da91f953435a (diff) | |
download | spark-33b837333435ceb0c04d1f361a5383c4fe6a5a75.tar.gz spark-33b837333435ceb0c04d1f361a5383c4fe6a5a75.tar.bz2 spark-33b837333435ceb0c04d1f361a5383c4fe6a5a75.zip |
[SPARK-11725][SQL] correctly handle null inputs for UDF
If user use primitive parameters in UDF, there is no way for him to do the null-check for primitive inputs, so we are assuming the primitive input is null-propagatable for this case and return null if the input is null.
Author: Wenchen Fan <wenchen@databricks.com>
Closes #9770 from cloud-fan/udf.
Diffstat (limited to 'sql')
6 files changed, 121 insertions, 1 deletions
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala index 0b3dd351e3..38828e59a2 100644 --- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala +++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala @@ -719,6 +719,15 @@ trait ScalaReflection { } } + /** + * Returns classes of input parameters of scala function object. + */ + def getParameterTypes(func: AnyRef): Seq[Class[_]] = { + val methods = func.getClass.getMethods.filter(m => m.getName == "apply" && !m.isBridge) + assert(methods.length == 1) + methods.head.getParameterTypes + } + def typeOfObject: PartialFunction[Any, DataType] = { // The data type can be determined without ambiguity. case obj: Boolean => BooleanType diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala index 2f4670b55b..f00c451b59 100644 --- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala +++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala @@ -25,7 +25,7 @@ import org.apache.spark.sql.catalyst.expressions.aggregate._ import org.apache.spark.sql.catalyst.plans.logical._ import org.apache.spark.sql.catalyst.rules._ import org.apache.spark.sql.catalyst.trees.TreeNodeRef -import org.apache.spark.sql.catalyst.{SimpleCatalystConf, CatalystConf} +import org.apache.spark.sql.catalyst.{ScalaReflection, SimpleCatalystConf, CatalystConf} import org.apache.spark.sql.types._ /** @@ -85,6 +85,8 @@ class Analyzer( extendedResolutionRules : _*), Batch("Nondeterministic", Once, PullOutNondeterministic), + Batch("UDF", Once, + HandleNullInputsForUDF), Batch("Cleanup", fixedPoint, CleanupAliases) ) @@ -1063,6 +1065,34 @@ class Analyzer( Project(p.output, newPlan.withNewChildren(newChild :: Nil)) } } + + /** + * Correctly handle null primitive inputs for UDF by adding extra [[If]] expression to do the + * null check. When user defines a UDF with primitive parameters, there is no way to tell if the + * primitive parameter is null or not, so here we assume the primitive input is null-propagatable + * and we should return null if the input is null. + */ + object HandleNullInputsForUDF extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan resolveOperators { + case p if !p.resolved => p // Skip unresolved nodes. + + case plan => plan transformExpressionsUp { + + case udf @ ScalaUDF(func, _, inputs, _) => + val parameterTypes = ScalaReflection.getParameterTypes(func) + assert(parameterTypes.length == inputs.length) + + val inputsNullCheck = parameterTypes.zip(inputs) + // TODO: skip null handling for not-nullable primitive inputs after we can completely + // trust the `nullable` information. + // .filter { case (cls, expr) => cls.isPrimitive && expr.nullable } + .filter { case (cls, _) => cls.isPrimitive } + .map { case (_, expr) => IsNull(expr) } + .reduceLeftOption[Expression]((e1, e2) => Or(e1, e2)) + inputsNullCheck.map(If(_, Literal.create(null, udf.dataType), udf)).getOrElse(udf) + } + } + } } /** diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUDF.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUDF.scala index 3388cc20a9..03b89221ef 100644 --- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUDF.scala +++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUDF.scala @@ -24,7 +24,13 @@ import org.apache.spark.sql.types.DataType /** * User-defined function. + * @param function The user defined scala function to run. + * Note that if you use primitive parameters, you are not able to check if it is + * null or not, and the UDF will return null for you if the primitive input is + * null. Use boxed type or [[Option]] if you wanna do the null-handling yourself. * @param dataType Return type of function. + * @param children The input expressions of this UDF. + * @param inputTypes The expected input types of this UDF. */ case class ScalaUDF( function: AnyRef, diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala index 3b848cfdf7..4ea410d492 100644 --- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala +++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala @@ -280,4 +280,21 @@ class ScalaReflectionSuite extends SparkFunSuite { assert(s.fields.map(_.dataType) === Seq(IntegerType, StringType, DoubleType)) } } + + test("get parameter type from a function object") { + val primitiveFunc = (i: Int, j: Long) => "x" + val primitiveTypes = getParameterTypes(primitiveFunc) + assert(primitiveTypes.forall(_.isPrimitive)) + assert(primitiveTypes === Seq(classOf[Int], classOf[Long])) + + val boxedFunc = (i: java.lang.Integer, j: java.lang.Long) => "x" + val boxedTypes = getParameterTypes(boxedFunc) + assert(boxedTypes.forall(!_.isPrimitive)) + assert(boxedTypes === Seq(classOf[java.lang.Integer], classOf[java.lang.Long])) + + val anyFunc = (i: Any, j: AnyRef) => "x" + val anyTypes = getParameterTypes(anyFunc) + assert(anyTypes.forall(!_.isPrimitive)) + assert(anyTypes === Seq(classOf[java.lang.Object], classOf[java.lang.Object])) + } } diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala index 65f09b46af..08586a9741 100644 --- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala +++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala @@ -174,4 +174,48 @@ class AnalysisSuite extends AnalysisTest { ) assertAnalysisError(plan, Seq("data type mismatch: Arguments must be same type")) } + + test("SPARK-11725: correctly handle null inputs for ScalaUDF") { + val string = testRelation2.output(0) + val double = testRelation2.output(2) + val short = testRelation2.output(4) + val nullResult = Literal.create(null, StringType) + + def checkUDF(udf: Expression, transformed: Expression): Unit = { + checkAnalysis( + Project(Alias(udf, "")() :: Nil, testRelation2), + Project(Alias(transformed, "")() :: Nil, testRelation2) + ) + } + + // non-primitive parameters do not need special null handling + val udf1 = ScalaUDF((s: String) => "x", StringType, string :: Nil) + val expected1 = udf1 + checkUDF(udf1, expected1) + + // only primitive parameter needs special null handling + val udf2 = ScalaUDF((s: String, d: Double) => "x", StringType, string :: double :: Nil) + val expected2 = If(IsNull(double), nullResult, udf2) + checkUDF(udf2, expected2) + + // special null handling should apply to all primitive parameters + val udf3 = ScalaUDF((s: Short, d: Double) => "x", StringType, short :: double :: Nil) + val expected3 = If( + IsNull(short) || IsNull(double), + nullResult, + udf3) + checkUDF(udf3, expected3) + + // we can skip special null handling for primitive parameters that are not nullable + // TODO: this is disabled for now as we can not completely trust `nullable`. + val udf4 = ScalaUDF( + (s: Short, d: Double) => "x", + StringType, + short :: double.withNullability(false) :: Nil) + val expected4 = If( + IsNull(short), + nullResult, + udf4) + // checkUDF(udf4, expected4) + } } diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala index 35cdab50bd..5a7f24684d 100644 --- a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala +++ b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala @@ -1115,4 +1115,18 @@ class DataFrameSuite extends QueryTest with SharedSQLContext { checkAnswer(df.select(df("*")), Row(1, "a")) checkAnswer(df.withColumnRenamed("d^'a.", "a"), Row(1, "a")) } + + test("SPARK-11725: correctly handle null inputs for ScalaUDF") { + val df = Seq( + new java.lang.Integer(22) -> "John", + null.asInstanceOf[java.lang.Integer] -> "Lucy").toDF("age", "name") + + val boxedUDF = udf[java.lang.Integer, java.lang.Integer] { + (i: java.lang.Integer) => if (i == null) null else i * 2 + } + checkAnswer(df.select(boxedUDF($"age")), Row(44) :: Row(null) :: Nil) + + val primitiveUDF = udf((i: Int) => i * 2) + checkAnswer(df.select(primitiveUDF($"age")), Row(44) :: Row(null) :: Nil) + } } |