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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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+++ 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"
+
+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)
+     : gc_grace_period_in_seconds_(gc_grace_period_in_seconds),
+       operands_limit_(operands_limit) {}
+
+ 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;
+
+ virtual const char* Name() const override;
+
+ virtual bool AllowSingleOperand() const override { return true; }
+
+ virtual bool ShouldMerge(const std::vector<Slice>& operands) const override {
+   return operands_limit_ > 0 && operands.size() >= operands_limit_;
+ }
+
+private:
+ int32_t gc_grace_period_in_seconds_;
+ size_t operands_limit_;
+};
+} // namespace cassandra
+}  // namespace ROCKSDB_NAMESPACE