thirdparty/patches/apache-arrow-7.0.0.patch

diff --git a/cpp/src/arrow/adapters/orc/adapter.cc b/cpp/src/arrow/adapters/orc/adapter.cc
index 03243e751..1eb9b2c81 100644
--- a/cpp/src/arrow/adapters/orc/adapter.cc
+++ b/cpp/src/arrow/adapters/orc/adapter.cc
@@ -47,9 +47,6 @@
 #include "arrow/util/visibility.h"
 #include "orc/Exceptions.hh"
 
-// alias to not interfere with nested orc namespace
-namespace liborc = orc;
-
 #define ORC_THROW_NOT_OK(s)                   \
   do {                                        \
     Status _s = (s);                          \
@@ -198,6 +195,8 @@ class ORCFileReader::Impl {
     return Init();
   }
 
+  virtual liborc::Reader* GetRawORCReader() { return reader_.get(); }
+
   Status Init() {
     int64_t nstripes = reader_->getNumberOfStripes();
     stripes_.resize(nstripes);
@@ -504,6 +503,32 @@ class ORCFileReader::Impl {
     return Status::OK();
   }
 
+  Result<std::shared_ptr<RecordBatchReader>> NextStripeReader(
+      int64_t batch_size, const std::vector<std::string>& include_names) {
+    if (current_row_ >= NumberOfRows()) {
+      return nullptr;
+    }
+
+    liborc::RowReaderOptions opts;
+    if (!include_names.empty()) {
+      RETURN_NOT_OK(SelectNames(&opts, include_names));
+    }
+    StripeInformation stripe_info({0, 0, 0, 0});
+    RETURN_NOT_OK(SelectStripeWithRowNumber(&opts, current_row_, &stripe_info));
+    std::shared_ptr<Schema> schema;
+    RETURN_NOT_OK(ReadSchema(opts, &schema));
+    std::unique_ptr<liborc::RowReader> row_reader;
+
+    ORC_BEGIN_CATCH_NOT_OK
+    row_reader = reader_->createRowReader(opts);
+    row_reader->seekToRow(current_row_);
+    current_row_ = stripe_info.first_row_of_stripe + stripe_info.num_rows;
+    ORC_END_CATCH_NOT_OK
+
+    return std::make_shared<OrcStripeReader>(std::move(row_reader), schema, batch_size,
+                                             pool_);
+  }
+
   Status NextStripeReader(int64_t batch_size, std::shared_ptr<RecordBatchReader>* out) {
     return NextStripeReader(batch_size, {}, out);
   }
@@ -531,6 +556,8 @@ Result<std::unique_ptr<ORCFileReader>> ORCFileReader::Open(
   return std::move(result);
 }
 
+liborc::Reader* ORCFileReader::GetRawORCReader() { return impl_->GetRawORCReader(); }
+
 Result<std::shared_ptr<const KeyValueMetadata>> ORCFileReader::ReadMetadata() {
   return impl_->ReadMetadata();
 }
@@ -653,6 +680,11 @@ Result<std::shared_ptr<RecordBatchReader>> ORCFileReader::NextStripeReader(
   return reader;
 }
 
+Result<std::shared_ptr<RecordBatchReader>> ORCFileReader::NextStripeReader(
+    int64_t batch_size, const std::vector<std::string>& include_names) {
+  return impl_->NextStripeReader(batch_size, include_names);
+}
+
 int64_t ORCFileReader::NumberOfStripes() { return impl_->NumberOfStripes(); }
 
 int64_t ORCFileReader::NumberOfRows() { return impl_->NumberOfRows(); }
diff --git a/cpp/src/arrow/adapters/orc/adapter.h b/cpp/src/arrow/adapters/orc/adapter.h
index 223efa515..04e6b0612 100644
--- a/cpp/src/arrow/adapters/orc/adapter.h
+++ b/cpp/src/arrow/adapters/orc/adapter.h
@@ -30,6 +30,10 @@
 #include "arrow/type_fwd.h"
 #include "arrow/util/macros.h"
 #include "arrow/util/visibility.h"
+#include "orc/Reader.hh"
+
+// alias to not interfere with nested orc namespace
+namespace liborc = orc;
 
 namespace arrow {
 namespace adapters {
@@ -51,6 +55,9 @@ class ARROW_EXPORT ORCFileReader {
   static Status Open(const std::shared_ptr<io::RandomAccessFile>& file, MemoryPool* pool,
                      std::unique_ptr<ORCFileReader>* reader);
 
+  /// \brief Get ORC reader from inside.
+  liborc::Reader* GetRawORCReader();
+
   /// \brief Creates a new ORC reader
   ///
   /// \param[in] file the data source
@@ -240,6 +247,19 @@ class ARROW_EXPORT ORCFileReader {
   Result<std::shared_ptr<RecordBatchReader>> NextStripeReader(
       int64_t batch_size, const std::vector<int>& include_indices);
 
+  /// \brief Get a stripe level record batch iterator with specified row count
+  ///         in each record batch. NextStripeReader serves as a fine grain
+  ///         alternative to ReadStripe which may cause OOM issue by loading
+  ///         the whole stripes into memory.
+  ///
+  /// \param[in] batch_size Get a stripe level record batch iterator with specified row
+  /// count in each record batch.
+  ///
+  /// \param[in] include_names the selected field names to read
+  /// \return the returned stripe reader
+  Result<std::shared_ptr<RecordBatchReader>> NextStripeReader(
+      int64_t batch_size, const std::vector<std::string>& include_names);
+
   /// \brief The number of stripes in the file
   int64_t NumberOfStripes();