mirror of https://github.com/facebook/rocksdb.git
44 lines
1.5 KiB
C++
44 lines
1.5 KiB
C++
// Copyright (c) 2017-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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#pragma once
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#include "rocksdb/merge_operator.h"
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#include "rocksdb/slice.h"
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#include "utilities/cassandra/cassandra_options.h"
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namespace ROCKSDB_NAMESPACE {
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namespace cassandra {
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/**
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* A MergeOperator for rocksdb that implements Cassandra row value merge.
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*/
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class CassandraValueMergeOperator : public MergeOperator {
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public:
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explicit CassandraValueMergeOperator(int32_t gc_grace_period_in_seconds,
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size_t operands_limit = 0);
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bool FullMergeV2(const MergeOperationInput& merge_in,
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MergeOperationOutput* merge_out) const override;
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bool PartialMergeMulti(const Slice& key,
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const std::deque<Slice>& operand_list,
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std::string* new_value, Logger* logger) const override;
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const char* Name() const override { return kClassName(); }
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static const char* kClassName() { return "CassandraValueMergeOperator"; }
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bool AllowSingleOperand() const override { return true; }
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bool ShouldMerge(const std::vector<Slice>& operands) const override {
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return options_.operands_limit > 0 &&
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operands.size() >= options_.operands_limit;
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}
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private:
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CassandraOptions options_;
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};
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} // namespace cassandra
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} // namespace ROCKSDB_NAMESPACE
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