diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala index 1140150f66864..adeeabffa76bb 100644 --- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala +++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala @@ -280,6 +280,12 @@ object HiveTypeCoercion { case p @ BinaryComparison(left @ DateType(), right @ TimestampType()) => p.makeCopy(Array(Cast(left, StringType), Cast(right, StringType))) + // Checking NullType + case p @ BinaryComparison(left @ StringType(), right @ NullType()) => + p.makeCopy(Array(left, Literal.create(null, StringType))) + case p @ BinaryComparison(left @ NullType(), right @ StringType()) => + p.makeCopy(Array(Literal.create(null, StringType), right)) + case p @ BinaryComparison(left @ StringType(), right) if right.dataType != StringType => p.makeCopy(Array(Cast(left, DoubleType), right)) case p @ BinaryComparison(left, right @ StringType()) if left.dataType != StringType => diff --git a/sql/core/src/test/scala/org/apache/spark/sql/ColumnExpressionSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/ColumnExpressionSuite.scala index fa559c9c64005..b6c7310f84208 100644 --- a/sql/core/src/test/scala/org/apache/spark/sql/ColumnExpressionSuite.scala +++ b/sql/core/src/test/scala/org/apache/spark/sql/ColumnExpressionSuite.scala @@ -368,6 +368,17 @@ class ColumnExpressionSuite extends QueryTest with SharedSQLContext { checkAnswer( nullData.filter($"a" <=> $"b"), Row(1, 1) :: Row(null, null) :: Nil) + + val nullData2 = sqlContext.createDataFrame(sparkContext.parallelize( + Row("abc") :: + Row(null) :: + Row("xyz") :: Nil), + StructType(Seq(StructField("a", StringType, true)))) + + checkAnswer( + nullData2.filter($"a" <=> null), + Row(null) :: Nil) + } test(">") {