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diff --git a/src/rocksdb/db/version_builder.h b/src/rocksdb/db/version_builder.h
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+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+#pragma once
+
+#include <memory>
+
+#include "rocksdb/file_system.h"
+#include "rocksdb/slice_transform.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+struct ImmutableCFOptions;
+class TableCache;
+class VersionStorageInfo;
+class VersionEdit;
+struct FileMetaData;
+class InternalStats;
+class Version;
+class VersionSet;
+class ColumnFamilyData;
+class CacheReservationManager;
+
+// A helper class so we can efficiently apply a whole sequence
+// of edits to a particular state without creating intermediate
+// Versions that contain full copies of the intermediate state.
+class VersionBuilder {
+ public:
+  VersionBuilder(const FileOptions& file_options,
+                 const ImmutableCFOptions* ioptions, TableCache* table_cache,
+                 VersionStorageInfo* base_vstorage, VersionSet* version_set,
+                 std::shared_ptr<CacheReservationManager>
+                     file_metadata_cache_res_mgr = nullptr);
+  ~VersionBuilder();
+
+  bool CheckConsistencyForNumLevels();
+  Status Apply(const VersionEdit* edit);
+  Status SaveTo(VersionStorageInfo* vstorage) const;
+  Status LoadTableHandlers(
+      InternalStats* internal_stats, int max_threads,
+      bool prefetch_index_and_filter_in_cache, bool is_initial_load,
+      const std::shared_ptr<const SliceTransform>& prefix_extractor,
+      size_t max_file_size_for_l0_meta_pin);
+  uint64_t GetMinOldestBlobFileNumber() const;
+
+ private:
+  class Rep;
+  std::unique_ptr<Rep> rep_;
+};
+
+// A wrapper of version builder which references the current version in
+// constructor and unref it in the destructor.
+// Both of the constructor and destructor need to be called inside DB Mutex.
+class BaseReferencedVersionBuilder {
+ public:
+  explicit BaseReferencedVersionBuilder(ColumnFamilyData* cfd);
+  BaseReferencedVersionBuilder(ColumnFamilyData* cfd, Version* v);
+  ~BaseReferencedVersionBuilder();
+  VersionBuilder* version_builder() const { return version_builder_.get(); }
+
+ private:
+  std::unique_ptr<VersionBuilder> version_builder_;
+  Version* version_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE