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diff --git a/src/rocksdb/include/rocksdb/utilities/debug.h b/src/rocksdb/include/rocksdb/utilities/debug.h
new file mode 100644
index 000000000..a2b6adcb0
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+++ b/src/rocksdb/include/rocksdb/utilities/debug.h
@@ -0,0 +1,49 @@
+//  Copyright (c) 2017-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).
+
+#pragma once
+
+#ifndef ROCKSDB_LITE
+
+#include "rocksdb/db.h"
+#include "rocksdb/types.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+// Data associated with a particular version of a key. A database may internally
+// store multiple versions of a same user key due to snapshots, compaction not
+// happening yet, etc.
+struct KeyVersion {
+  KeyVersion() : user_key(""), value(""), sequence(0), type(0) {}
+
+  KeyVersion(const std::string& _user_key, const std::string& _value,
+             SequenceNumber _sequence, int _type)
+      : user_key(_user_key), value(_value), sequence(_sequence), type(_type) {}
+
+  std::string user_key;
+  std::string value;
+  SequenceNumber sequence;
+  // TODO(ajkr): we should provide a helper function that converts the int to a
+  // string describing the type for easier debugging.
+  int type;
+};
+
+// Returns listing of all versions of keys in the provided user key range.
+// The range is inclusive-inclusive, i.e., [`begin_key`, `end_key`], or
+// `max_num_ikeys` has been reached. Since all those keys returned will be
+// copied to memory, if the range covers too many keys, the memory usage
+// may be huge. `max_num_ikeys` can be used to cap the memory usage.
+// The result is inserted into the provided vector, `key_versions`.
+Status GetAllKeyVersions(DB* db, Slice begin_key, Slice end_key,
+                         size_t max_num_ikeys,
+                         std::vector<KeyVersion>* key_versions);
+
+Status GetAllKeyVersions(DB* db, ColumnFamilyHandle* cfh, Slice begin_key,
+                         Slice end_key, size_t max_num_ikeys,
+                         std::vector<KeyVersion>* key_versions);
+
+}  // namespace ROCKSDB_NAMESPACE
+
+#endif  // ROCKSDB_LITE