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diff --git a/src/rocksdb/utilities/cassandra/merge_operator.h b/src/rocksdb/utilities/cassandra/merge_operator.h
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+//  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
+#include "rocksdb/merge_operator.h"
+#include "rocksdb/slice.h"
+#include "utilities/cassandra/cassandra_options.h"
+
+namespace ROCKSDB_NAMESPACE {
+namespace cassandra {
+
+/**
+ * A MergeOperator for rocksdb that implements Cassandra row value merge.
+ */
+class CassandraValueMergeOperator : public MergeOperator {
+ public:
+  explicit CassandraValueMergeOperator(int32_t gc_grace_period_in_seconds,
+                                       size_t operands_limit = 0);
+
+  virtual bool FullMergeV2(const MergeOperationInput& merge_in,
+                           MergeOperationOutput* merge_out) const override;
+
+  virtual bool PartialMergeMulti(const Slice& key,
+                                 const std::deque<Slice>& operand_list,
+                                 std::string* new_value,
+                                 Logger* logger) const override;
+
+  const char* Name() const override { return kClassName(); }
+  static const char* kClassName() { return "CassandraValueMergeOperator"; }
+
+  virtual bool AllowSingleOperand() const override { return true; }
+
+  virtual bool ShouldMerge(const std::vector<Slice>& operands) const override {
+    return options_.operands_limit > 0 &&
+           operands.size() >= options_.operands_limit;
+  }
+
+ private:
+  CassandraOptions options_;
+};
+}  // namespace cassandra
+}  // namespace ROCKSDB_NAMESPACE