diff --git a/velox/connectors/hive/HiveDataSource.cpp b/velox/connectors/hive/HiveDataSource.cpp
index dbac54e81889..8f1fa311e6c9 100644
--- a/velox/connectors/hive/HiveDataSource.cpp
+++ b/velox/connectors/hive/HiveDataSource.cpp
@@ -323,6 +323,7 @@ void HiveDataSource::addSplit(std::shared_ptr<ConnectorSplit> split) {
   // so we initialize it beforehand.
   splitReader_->configureReaderOptions(randomSkip_);
   splitReader_->prepareSplit(metadataFilter_, runtimeStats_);
+  readerOutputType_ = splitReader_->readerOutputType();
 }
 
 vector_size_t HiveDataSource::applyBucketConversion(
@@ -378,7 +379,12 @@ std::optional<RowVectorPtr> HiveDataSource::next(
     return nullptr;
   }
 
-  if (!output_) {
+  // Bucket conversion or delta update could add extra column to reader output.
+  auto needsExtraColumn = [&] {
+    return output_->asUnchecked<RowVector>()->childrenSize() <
+        readerOutputType_->size();
+  };
+  if (!output_ || needsExtraColumn()) {
     output_ = BaseVector::create(readerOutputType_, 0, pool_);
   }
 
diff --git a/velox/connectors/hive/SplitReader.cpp b/velox/connectors/hive/SplitReader.cpp
index ebbb543e0e54..572e47360b19 100644
--- a/velox/connectors/hive/SplitReader.cpp
+++ b/velox/connectors/hive/SplitReader.cpp
@@ -147,7 +147,11 @@ void SplitReader::configureReaderOptions(
 void SplitReader::prepareSplit(
     std::shared_ptr<common::MetadataFilter> metadataFilter,
     dwio::common::RuntimeStatistics& runtimeStats) {
-  auto rowType = createReader();
+  createReader();
+  if (emptySplit_) {
+    return;
+  }
+  auto rowType = getAdaptedRowType();
 
   if (checkIfSplitIsEmpty(runtimeStats)) {
     VELOX_CHECK(emptySplit_);
@@ -221,7 +225,7 @@ std::string SplitReader::toString() const {
       static_cast<const void*>(baseRowReader_.get()));
 }
 
-RowTypePtr SplitReader::createReader() {
+void SplitReader::createReader() {
   VELOX_CHECK_NE(
       baseReaderOpts_.fileFormat(), dwio::common::FileFormat::UNKNOWN);
 
@@ -237,7 +241,7 @@ RowTypePtr SplitReader::createReader() {
         hiveConfig_->ignoreMissingFiles(
             connectorQueryCtx_->sessionProperties())) {
       emptySplit_ = true;
-      return nullptr;
+      return;
     }
     throw;
   }
@@ -258,7 +262,9 @@ RowTypePtr SplitReader::createReader() {
 
   baseReader_ = dwio::common::getReaderFactory(baseReaderOpts_.fileFormat())
                     ->createReader(std::move(baseFileInput), baseReaderOpts_);
+}
 
+RowTypePtr SplitReader::getAdaptedRowType() const {
   auto& fileType = baseReader_->rowType();
   auto columnTypes = adaptColumns(fileType, baseReaderOpts_.fileSchema());
   auto columnNames = fileType->names();
diff --git a/velox/connectors/hive/SplitReader.h b/velox/connectors/hive/SplitReader.h
index 5466107ca620..debf5831ef57 100644
--- a/velox/connectors/hive/SplitReader.h
+++ b/velox/connectors/hive/SplitReader.h
@@ -95,6 +95,10 @@ class SplitReader {
 
   void setConnectorQueryCtx(const ConnectorQueryCtx* connectorQueryCtx);
 
+  const RowTypePtr& readerOutputType() const {
+    return readerOutputType_;
+  }
+
   std::string toString() const;
 
  protected:
@@ -113,7 +117,11 @@ class SplitReader {
 
   /// Create the dwio::common::Reader object baseReader_, which will be used to
   /// read the data file's metadata and schema
-  RowTypePtr createReader();
+  void createReader();
+
+  // Adjust the scan spec according to the current split, then return the
+  // adapted row type.
+  RowTypePtr getAdaptedRowType() const;
 
   // Check if the filters pass on the column statistics.  When delta update is
   // present, the corresonding filter should be disabled before calling this
@@ -155,7 +163,7 @@ class SplitReader {
   const ConnectorQueryCtx* connectorQueryCtx_;
   const std::shared_ptr<const HiveConfig> hiveConfig_;
 
-  const RowTypePtr readerOutputType_;
+  RowTypePtr readerOutputType_;
   const std::shared_ptr<io::IoStatistics> ioStats_;
   FileHandleFactory* const fileHandleFactory_;
   folly::Executor* const executor_;
diff --git a/velox/connectors/hive/iceberg/IcebergSplitReader.cpp b/velox/connectors/hive/iceberg/IcebergSplitReader.cpp
index dd8c059a53ef..e96223b8cacf 100644
--- a/velox/connectors/hive/iceberg/IcebergSplitReader.cpp
+++ b/velox/connectors/hive/iceberg/IcebergSplitReader.cpp
@@ -55,7 +55,11 @@ IcebergSplitReader::IcebergSplitReader(
 void IcebergSplitReader::prepareSplit(
     std::shared_ptr<common::MetadataFilter> metadataFilter,
     dwio::common::RuntimeStatistics& runtimeStats) {
-  auto rowType = createReader();
+  createReader();
+  if (emptySplit_) {
+    return;
+  }
+  auto rowType = getAdaptedRowType();
 
   if (checkIfSplitIsEmpty(runtimeStats)) {
     VELOX_CHECK(emptySplit_);
diff --git a/velox/dwio/common/Reader.cpp b/velox/dwio/common/Reader.cpp
index eb21b67b1882..7d6ee8012ae5 100644
--- a/velox/dwio/common/Reader.cpp
+++ b/velox/dwio/common/Reader.cpp
@@ -49,6 +49,7 @@ VectorPtr RowReader::projectColumns(
     }
   }
   for (auto& childSpec : spec.children()) {
+    VELOX_CHECK_NULL(childSpec->deltaUpdate());
     VectorPtr child;
     if (childSpec->isConstant()) {
       child = BaseVector::wrapInConstant(
@@ -133,7 +134,7 @@ void RowReader::readWithRowNumber(
   const auto& rowNumberColumnName = rowNumberColumnInfo->name;
   column_index_t numChildren{0};
   for (auto& column : options.scanSpec()->children()) {
-    if (column->projectOut()) {
+    if (column->keepValues()) {
       ++numChildren;
     }
   }
diff --git a/velox/dwio/common/ScanSpec.h b/velox/dwio/common/ScanSpec.h
index 67744a783c7d..a040fc5316bd 100644
--- a/velox/dwio/common/ScanSpec.h
+++ b/velox/dwio/common/ScanSpec.h
@@ -162,7 +162,7 @@ class ScanSpec {
   }
 
   bool keepValues() const {
-    return projectOut_;
+    return projectOut_ || deltaUpdate_;
   }
 
   // Position in the RowVector returned by the top level scan. Applies
diff --git a/velox/dwio/common/SelectiveStructColumnReader.cpp b/velox/dwio/common/SelectiveStructColumnReader.cpp
index a07b04b14355..4401e73977bb 100644
--- a/velox/dwio/common/SelectiveStructColumnReader.cpp
+++ b/velox/dwio/common/SelectiveStructColumnReader.cpp
@@ -487,7 +487,7 @@ void SelectiveStructColumnReaderBase::getValues(
   setComplexNulls(rows, *result);
   for (const auto& childSpec : scanSpec_->children()) {
     VELOX_TRACE_HISTORY_PUSH("getValues %s", childSpec->fieldName().c_str());
-    if (!childSpec->projectOut()) {
+    if (!childSpec->keepValues()) {
       continue;
     }