[GLUTEN-11622][VL] Add basic TIMESTAMP_NTZ type support

backends-velox/src-delta33/test/scala/org/apache/spark/sql/delta/DeltaInsertIntoTableSuite.scala

@@ -1423,7 +1423,8 @@ abstract class DeltaInsertIntoTests(
     }
   }
 
-  test("insertInto: Timestamp No Timezone round trips across timezones") {
+  // Cast from TIMESTAMP_NTZ to TIMESTAMP has not been supported.
+  ignore("insertInto: Timestamp No Timezone round trips across timezones") {
     val t1 = "timestamp_ntz"
     withTable(t1) {
       withTimeZone("GMT-8") {

backends-velox/src/main/scala/org/apache/gluten/backendsapi/velox/VeloxValidatorApi.scala

@@ -113,7 +113,7 @@ object VeloxValidatorApi {
         true
       case dt
           if !enableTimestampNtzValidation &&
-            dt.getClass.getSimpleName == "TimestampNTZType" =>
+            dt.typeName == "timestamp_ntz" =>
         // Allow TimestampNTZ when validation is disabled (for development/testing)
         // Use reflection to avoid compile-time dependency on Spark 3.4+ TimestampNTZType
         true

backends-velox/src/main/scala/org/apache/gluten/config/VeloxConfig.scala

@@ -767,5 +767,5 @@ object VeloxConfig extends ConfigRegistry {
           "containing TimestampNTZ will fall back to Spark execution. Set to false during " +
           "development/testing of TimestampNTZ support to allow native execution.")
       .booleanConf
-      .createWithDefault(true)
+      .createWithDefault(false)
 }

backends-velox/src/main/scala/org/apache/gluten/execution/VeloxColumnarToRowExec.scala

@@ -50,6 +50,7 @@ case class VeloxColumnarToRowExec(child: SparkPlan) extends ColumnarToRowExecBas
         case _: DoubleType =>
         case _: StringType =>
         case _: TimestampType =>
+        case other if other.typeName == "timestamp_ntz" =>
         case _: DateType =>
         case _: BinaryType =>
         case _: DecimalType =>

backends-velox/src/test/scala/org/apache/gluten/execution/FallbackSuite.scala

@@ -272,7 +272,7 @@ class FallbackSuite extends VeloxWholeStageTransformerSuite with AdaptiveSparkPl
     }
   }
 
-  test("fallback with index based schema evolution") {
+  testWithMinSparkVersion("fallback with index based schema evolution", "3.4") {
     val query = "SELECT c2 FROM test"
     Seq("parquet", "orc").foreach {
       format =>
@@ -295,9 +295,7 @@ class FallbackSuite extends VeloxWholeStageTransformerSuite with AdaptiveSparkPl
                     runQueryAndCompare(query) {
                       df =>
                         val plan = df.queryExecution.executedPlan
-                        val fallback = parquetUseColumnNames == "false" ||
-                          orcUseColumnNames == "false"
-                        assert(collect(plan) { case g: GlutenPlan => g }.isEmpty == fallback)
+                        assert(collect(plan) { case g: GlutenPlan => g }.nonEmpty)
                     }
                   }
                 }

backends-velox/src/test/scala/org/apache/gluten/execution/VeloxParquetDataTypeValidationSuite.scala

@@ -19,6 +19,7 @@ package org.apache.gluten.execution
 import org.apache.gluten.config.GlutenConfig
 
 import org.apache.spark.SparkConf
+import org.apache.spark.sql.Row
 
 import java.io.File
 
@@ -465,17 +466,17 @@ class VeloxParquetDataTypeValidationSuite extends VeloxWholeStageTransformerSuit
     }
   }
 
-  testWithMinSparkVersion("Fallback for TimestampNTZ type scan", "3.4") {
+  testWithMinSparkVersion("TimestampNTZ type scan", "3.4") {
     withTempDir {
       dir =>
         val path = new File(dir, "ntz_data").toURI.getPath
         val inputDf =
           spark.sql("SELECT CAST('2024-01-01 00:00:00' AS TIMESTAMP_NTZ) AS ts_ntz")
         inputDf.write.format("parquet").save(path)
-        val df = spark.read.format("parquet").load(path)
+        val df = spark.read.parquet(path)
         val executedPlan = getExecutedPlan(df)
-        assert(!executedPlan.exists(plan => plan.isInstanceOf[BatchScanExecTransformer]))
-        checkAnswer(df, inputDf)
+        assert(executedPlan.exists(plan => plan.isInstanceOf[BatchScanExecTransformer]))
+        checkAnswer(df, Seq(Row(java.time.LocalDateTime.of(2024, 1, 1, 0, 0, 0, 0))))
     }
   }
 

backends-velox/src/test/scala/org/apache/gluten/functions/DateFunctionsValidateSuite.scala

@@ -16,7 +16,7 @@
  */
 package org.apache.gluten.functions
 
-import org.apache.gluten.execution.ProjectExecTransformer
+import org.apache.gluten.execution.{BatchScanExecTransformer, ProjectExecTransformer}
 
 import org.apache.spark.sql.execution.ProjectExec
 import org.apache.spark.sql.types.Decimal
@@ -569,4 +569,43 @@ class DateFunctionsValidateSuite extends FunctionsValidateSuite {
     }
   }
 
+  testWithMinSparkVersion("read as timestamp_ntz", "3.4") {
+    val inputs: Seq[String] = Seq(
+      "1970-01-01",
+      "1970-01-01 00:00:00-02:00",
+      "1970-01-01 00:00:00 +02:00",
+      "2000-01-01",
+      "1970-01-01 00:00:00",
+      "2000-01-01 12:21:56",
+      "2015-03-18T12:03:17Z",
+      "2015-03-18 12:03:17",
+      "2015-03-18T12:03:17",
+      "2015-03-18 12:03:17.123",
+      "2015-03-18T12:03:17.123",
+      "2015-03-18T12:03:17.456",
+      "2015-03-18 12:03:17.456"
+    )
+
+    withTempPath {
+      dir =>
+        val path = dir.getAbsolutePath
+        val inputDF = spark.createDataset(inputs).toDF("input")
+        val df = inputDF.selectExpr("cast(input as timestamp_ntz) as ts")
+        df.coalesce(1).write.mode("overwrite").parquet(path)
+        val readDf = spark.read.parquet(path)
+        readDf.createOrReplaceTempView("view")
+
+        runQueryAndCompare("select * from view") {
+          checkGlutenPlan[BatchScanExecTransformer]
+        }
+
+        // Ensures the fallback of unsupported function works.
+        runQueryAndCompare("select hour(ts) from view") {
+          df =>
+            assert(collect(df.queryExecution.executedPlan) {
+              case p if p.isInstanceOf[ProjectExec] => p
+            }.nonEmpty)
+        }
+    }
+  }
 }

cpp/velox/substrait/SubstraitParser.cc

@@ -17,9 +17,8 @@
 
 #include "SubstraitParser.h"
 #include "TypeUtils.h"
-#include "velox/common/base/Exceptions.h"
-
 #include "VeloxSubstraitSignature.h"
+#include "velox/common/base/Exceptions.h"
 
 namespace gluten {
 
@@ -78,6 +77,8 @@ TypePtr SubstraitParser::parseType(const ::substrait::Type& substraitType, bool
       return DATE();
     case ::substrait::Type::KindCase::kTimestampTz:
       return TIMESTAMP();
+    case ::substrait::Type::KindCase::kTimestamp:
+      return TIMESTAMP_UTC();
     case ::substrait::Type::KindCase::kDecimal: {
       auto precision = substraitType.decimal().precision();
       auto scale = substraitType.decimal().scale();
@@ -356,6 +357,9 @@ int64_t SubstraitParser::getLiteralValue(const ::substrait::Expression::Literal&
     memcpy(&decimalValue, decimal.c_str(), 16);
     return static_cast<int64_t>(decimalValue);
   }
+  if (literal.has_timestamp()) {
+    return literal.timestamp();
+  }
   return literal.i64();
 }
 

cpp/velox/substrait/SubstraitToVeloxExpr.cc

@@ -17,11 +17,10 @@
 
 #include "SubstraitToVeloxExpr.h"
 #include "TypeUtils.h"
+#include "velox/type/Timestamp.h"
 #include "velox/vector/FlatVector.h"
 #include "velox/vector/VariantToVector.h"
 
-#include "velox/type/Timestamp.h"
-
 using namespace facebook::velox;
 
 namespace {
@@ -133,6 +132,8 @@ TypePtr getScalarType(const ::substrait::Expression::Literal& literal) {
       return DATE();
     case ::substrait::Expression_Literal::LiteralTypeCase::kTimestampTz:
       return TIMESTAMP();
+    case ::substrait::Expression_Literal::LiteralTypeCase::kTimestamp:
+      return TIMESTAMP_UTC();
     case ::substrait::Expression_Literal::LiteralTypeCase::kString:
       return VARCHAR();
     case ::substrait::Expression_Literal::LiteralTypeCase::kVarChar:

cpp/velox/substrait/SubstraitToVeloxPlan.cc

@@ -28,6 +28,7 @@
 
 #include "utils/ConfigExtractor.h"
 #include "utils/ObjectStore.h"
+#include "utils/VeloxArrowUtils.h"
 #include "utils/VeloxWriterUtils.h"
 
 #include "config.pb.h"

ep/build-velox/src/get-velox.sh

@@ -18,7 +18,7 @@ set -exu
 
 CURRENT_DIR=$(cd "$(dirname "$BASH_SOURCE")"; pwd)
 VELOX_REPO=https://github.com/IBM/velox.git
-VELOX_BRANCH=dft-2026_04_13
+VELOX_BRANCH=ts_ntz_ibm
 VELOX_ENHANCED_BRANCH=ibm-2026_04_13
 VELOX_HOME=""
 RUN_SETUP_SCRIPT=ON

gluten-arrow/src/main/scala/org/apache/spark/sql/utils/SparkArrowUtil.scala

@@ -50,7 +50,7 @@ object SparkArrowUtil {
       } else {
         new ArrowType.Timestamp(TimeUnit.MICROSECOND, "UTC")
       }
-    case dt if dt.catalogString == "timestamp_ntz" =>
+    case dt if dt.typeName == "timestamp_ntz" =>
       new ArrowType.Timestamp(TimeUnit.MICROSECOND, null)
     case YearMonthIntervalType.DEFAULT =>
       new ArrowType.Interval(IntervalUnit.YEAR_MONTH)
@@ -168,8 +168,6 @@ object SparkArrowUtil {
     }.asJava)
   }
 
-  // TimestampNTZ is not supported for native computation, but the Arrow type mapping is needed
-  // for row-to-columnar transitions when the fallback validator tags NTZ operators.
   def checkSchema(schema: StructType): Boolean = {
     try {
       SparkSchemaUtil.toArrowSchema(schema)

gluten-delta/src/test/scala/org/apache/gluten/execution/DeltaSuite.scala

@@ -340,13 +340,13 @@ abstract class DeltaSuite extends WholeStageTransformerSuite {
 
   // TIMESTAMP_NTZ was introduced in Spark 3.4 / Delta 2.4
   testWithMinSparkVersion(
-    "delta: create table with TIMESTAMP_NTZ should fallback and return correct results",
+    "delta: create table with TIMESTAMP_NTZ and return correct results",
     "3.4") {
     withTable("delta_ntz") {
       spark.sql("CREATE TABLE delta_ntz(c1 STRING, c2 TIMESTAMP, c3 TIMESTAMP_NTZ) USING DELTA")
       spark.sql("""INSERT INTO delta_ntz VALUES
                   |('foo','2022-01-02 03:04:05.123456','2022-01-02 03:04:05.123456')""".stripMargin)
-      val df = runQueryAndCompare("select * from delta_ntz", noFallBack = false) { _ => }
+      val df = runQueryAndCompare("select * from delta_ntz") { _ => }
       checkAnswer(
         df,
         Row(

gluten-substrait/src/main/java/org/apache/gluten/substrait/expression/TimestampNTZLiteralNode.java

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gluten.substrait.expression;
+
+import org.apache.gluten.substrait.type.TimestampTypeNode;
+import org.apache.gluten.substrait.type.TypeNode;
+
+import io.substrait.proto.Expression.Literal.Builder;
+
+public class TimestampNTZLiteralNode extends LiteralNodeWithValue<Long> {
+  public TimestampNTZLiteralNode(Long value) {
+    super(value, new TimestampTypeNode(true));
+  }
+
+  public TimestampNTZLiteralNode(Long value, TypeNode typeNode) {
+    super(value, typeNode);
+  }
+
+  @Override
+  protected void updateLiteralBuilder(Builder literalBuilder, Long value) {
+    literalBuilder.setTimestamp(value);
+  }
+}

gluten-substrait/src/main/java/org/apache/gluten/substrait/type/TimestampNTZTypeNode.java

@@ -0,0 +1,40 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gluten.substrait.type;
+
+import io.substrait.proto.Type;
+
+public class TimestampNTZTypeNode extends TypeNode {
+
+  public TimestampNTZTypeNode(Boolean nullable) {
+    super(nullable);
+  }
+
+  @Override
+  public Type toProtobuf() {
+    Type.Timestamp.Builder timestampBuilder = Type.Timestamp.newBuilder();
+    if (nullable) {
+      timestampBuilder.setNullability(Type.Nullability.NULLABILITY_NULLABLE);
+    } else {
+      timestampBuilder.setNullability(Type.Nullability.NULLABILITY_REQUIRED);
+    }
+
+    Type.Builder builder = Type.newBuilder();
+    builder.setTimestamp(timestampBuilder.build());
+    return builder.build();
+  }
+}

gluten-substrait/src/main/java/org/apache/gluten/substrait/type/TypeBuilder.java

@@ -81,6 +81,10 @@ public static TypeNode makeTimestamp(Boolean nullable) {
     return new TimestampTypeNode(nullable);
   }
 
+  public static TypeNode makeTimestampNTZ(Boolean nullable) {
+    return new TimestampNTZTypeNode(nullable);
+  }
+
   public static TypeNode makeStruct(Boolean nullable, List<TypeNode> types, List<String> names) {
     return new StructNode(nullable, types, names);
   }

gluten-substrait/src/main/scala/org/apache/gluten/expression/ConverterUtils.scala

@@ -160,6 +160,19 @@ object ConverterUtils extends Logging {
         (StringType, isNullable(substraitType.getString.getNullability))
       case Type.KindCase.BINARY =>
         (BinaryType, isNullable(substraitType.getBinary.getNullability))
+      case Type.KindCase.TIMESTAMP =>
+        try {
+          (
+            Class
+              .forName("org.apache.spark.sql.types.TimestampNTZType$")
+              .getField("MODULE$")
+              .get(null)
+              .asInstanceOf[DataType],
+            isNullable(substraitType.getTimestamp.getNullability))
+        } catch {
+          case _: ClassNotFoundException =>
+            throw new GlutenNotSupportException(s"Type $substraitType not supported.")
+        }
       case Type.KindCase.TIMESTAMP_TZ =>
         (TimestampType, isNullable(substraitType.getTimestampTz.getNullability))
       case Type.KindCase.DATE =>
@@ -226,6 +239,8 @@ object ConverterUtils extends Logging {
         TypeBuilder.makeDecimal(nullable, precision, scale)
       case TimestampType =>
         TypeBuilder.makeTimestamp(nullable)
+      case other if other.typeName == "timestamp_ntz" =>
+        TypeBuilder.makeTimestampNTZ(nullable)
       case m: MapType =>
         TypeBuilder.makeMap(
           nullable,
@@ -399,6 +414,7 @@ object ConverterUtils extends Logging {
       case DoubleType => "fp64"
       case DateType => "date"
       case TimestampType => "ts"
+      case other if other.typeName == "timestamp_ntz" => "ts_ntz"
       case StringType => "str"
       case BinaryType => "vbin"
       case DecimalType() =>