Use unique pointer in OrcGroup::pax_columns_

The function OrcGroup::GetColumnValue() has a critical performance
issue cause by shared smart pointer. This commit replace the shared
pointer by unique pointer to eliminate the lock issue.

Author: gfphoenix78

contrib/pax_storage/src/cpp/storage/micro_partition.h

@@ -181,7 +181,7 @@ class MicroPartitionReader {
     // fetch, compression/encoding. At the same time, pax column can also be
     // used as a general interface for internal using, because it's zero copy
     // from buffer. more details in `storage/columns`
-    virtual const std::shared_ptr<PaxColumns> &GetAllColumns() const = 0;
+    virtual const std::unique_ptr<PaxColumns> &GetAllColumns() const = 0;
 
     virtual void SetVisibilityMap(
         std::shared_ptr<Bitmap8> visibility_bitmap) = 0;

contrib/pax_storage/src/cpp/storage/orc/orc_group.cc

@@ -64,7 +64,7 @@ inline static std::pair<Datum, bool> GetColumnDatum(PaxColumn *column,
   return {rc, false};
 }
 
-OrcGroup::OrcGroup(std::unique_ptr<PaxColumns> &&pax_column, size_t row_offset,
+OrcGroup::OrcGroup(std::unique_ptr<PaxColumns> pax_column, size_t row_offset,
                    const std::vector<int> *proj_col_index,
                    std::shared_ptr<Bitmap8> micro_partition_visibility_bitmap)
     : pax_columns_(std::move(pax_column)),
@@ -88,7 +88,7 @@ size_t OrcGroup::GetRows() const { return pax_columns_->GetRows(); }
 
 size_t OrcGroup::GetRowOffset() const { return row_offset_; }
 
-const std::shared_ptr<PaxColumns> &OrcGroup::GetAllColumns() const {
+const std::unique_ptr<PaxColumns> &OrcGroup::GetAllColumns() const {
   return pax_columns_;
 }
 

contrib/pax_storage/src/cpp/storage/orc/orc_group.h

@@ -40,7 +40,7 @@ class OrcDumpReader;
 class OrcGroup : public MicroPartitionReader::Group {
  public:
   OrcGroup(
-      std::unique_ptr<PaxColumns> &&pax_column, size_t row_offset,
+      std::unique_ptr<PaxColumns> pax_column, size_t row_offset,
       const std::vector<int> *proj_col_index,
       std::shared_ptr<Bitmap8> micro_partition_visibility_bitmap = nullptr);
 
@@ -50,7 +50,7 @@ class OrcGroup : public MicroPartitionReader::Group {
 
   size_t GetRowOffset() const override;
 
-  const std::shared_ptr<PaxColumns> &GetAllColumns() const override;
+  const std::unique_ptr<PaxColumns> &GetAllColumns() const override;
 
   virtual std::pair<bool, size_t> ReadTuple(TupleTableSlot *slot) override;
 
@@ -74,7 +74,7 @@ class OrcGroup : public MicroPartitionReader::Group {
                                                  size_t row_index);
 
  protected:
-  std::shared_ptr<PaxColumns> pax_columns_;
+  std::unique_ptr<PaxColumns> pax_columns_;
   std::shared_ptr<Bitmap8> micro_partition_visibility_bitmap_;
   size_t row_offset_;
   size_t current_row_index_;