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diff --git a/src/rocksdb/include/rocksdb/stats_history.h b/src/rocksdb/include/rocksdb/stats_history.h
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+++ b/src/rocksdb/include/rocksdb/stats_history.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 <map>
+#include <string>
+
+#include "rocksdb/statistics.h"
+#include "rocksdb/status.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+class DBImpl;
+
+// StatsHistoryIterator is the main interface for users to programmatically
+// access statistics snapshots that was automatically stored by RocksDB.
+// Depending on options, the stats can be in memory or on disk.
+// The stats snapshots are indexed by time that they were recorded, and each
+// stats snapshot contains individual stat name and value at the time of
+// recording.
+// Example:
+//   std::unique_ptr<StatsHistoryIterator> stats_iter;
+//   Status s = db->GetStatsHistory(0 /* start_time */,
+//                                  env->NowMicros() /* end_time*/,
+//                                  &stats_iter);
+//   if (s.ok) {
+//     for (; stats_iter->Valid(); stats_iter->Next()) {
+//       uint64_t stats_time = stats_iter->GetStatsTime();
+//       const std::map<std::string, uint64_t>& stats_map =
+//           stats_iter->GetStatsMap();
+//       process(stats_time, stats_map);
+//     }
+//   }
+class StatsHistoryIterator {
+ public:
+  StatsHistoryIterator() {}
+  virtual ~StatsHistoryIterator() {}
+
+  virtual bool Valid() const = 0;
+
+  // Moves to the next stats history record.  After this call, Valid() is
+  // true iff the iterator was not positioned at the last entry in the source.
+  // REQUIRES: Valid()
+  virtual void Next() = 0;
+
+  // Return the time stamp (in seconds) when stats history is recorded.
+  // REQUIRES: Valid()
+  virtual uint64_t GetStatsTime() const = 0;
+
+  // DEPRECATED (was never used)
+  virtual int GetFormatVersion() const { return -1; }
+
+  // Return the current stats history as an std::map which specifies the
+  // mapping from stats name to stats value . The underlying storage
+  // for the returned map is valid only until the next modification of
+  // the iterator.
+  // REQUIRES: Valid()
+  virtual const std::map<std::string, uint64_t>& GetStatsMap() const = 0;
+
+  // If an error has occurred, return it.  Else return an ok status.
+  virtual Status status() const = 0;
+};
+
+}  // namespace ROCKSDB_NAMESPACE