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Diffstat (limited to 'src/rocksdb/utilities/cassandra/merge_operator.h')
-rw-r--r-- | src/rocksdb/utilities/cassandra/merge_operator.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/src/rocksdb/utilities/cassandra/merge_operator.h b/src/rocksdb/utilities/cassandra/merge_operator.h new file mode 100644 index 000000000..af8725db7 --- /dev/null +++ b/src/rocksdb/utilities/cassandra/merge_operator.h @@ -0,0 +1,44 @@ +// 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 |