rocksdb/include/rocksdb/sst_file_writer.h
Islam AbdelRahman f03b5c987b Add experimental DB::AddFile() to plug sst files into empty DB
Summary:
This is an initial version of bulk load feature

This diff allow us to create sst files, and then bulk load them later, right now the restrictions for loading an sst file are
(1) Memtables are empty
(2) Added sst files have sequence number = 0, and existing values in database have sequence number = 0
(3) Added sst files values are not overlapping

Test Plan: unit testing

Reviewers: igor, ott, sdong

Reviewed By: sdong

Subscribers: leveldb, ott, dhruba

Differential Revision: https://reviews.facebook.net/D39081
2015-09-23 12:42:43 -07:00

78 lines
2.8 KiB
C++

// Copyright (c) 2015, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
#pragma once
#include <string>
#include "rocksdb/env.h"
#include "rocksdb/immutable_options.h"
#include "rocksdb/types.h"
namespace rocksdb {
class Comparator;
// Table Properties that are specific to tables created by SstFileWriter.
struct ExternalSstFilePropertyNames {
// value of this property is a fixed int32 number.
static const std::string kVersion;
};
// ExternalSstFileInfo include information about sst files created
// using SstFileWriter
struct ExternalSstFileInfo {
ExternalSstFileInfo() {}
ExternalSstFileInfo(const std::string& _file_path,
const std::string& _smallest_key,
const std::string& _largest_key,
SequenceNumber _sequence_number, uint64_t _file_size,
int32_t _num_entries, int32_t _version)
: file_path(_file_path),
smallest_key(_smallest_key),
largest_key(_largest_key),
sequence_number(_sequence_number),
file_size(_file_size),
num_entries(_num_entries),
version(_version) {}
std::string file_path; // external sst file path
std::string smallest_key; // smallest user key in file
std::string largest_key; // largest user key in file
SequenceNumber sequence_number; // sequence number of all keys in file
uint64_t file_size; // file size in bytes
uint64_t num_entries; // number of entries in file
int32_t version; // file version
};
// SstFileWriter is used to create sst files that can be added to database later
// All keys in files generated by SstFileWriter will have sequence number = 0
class SstFileWriter {
public:
SstFileWriter(const EnvOptions& env_options,
const ImmutableCFOptions& ioptions,
const Comparator* user_comparator);
~SstFileWriter();
// Prepare SstFileWriter to write into file located at "file_path".
Status Open(const std::string& file_path);
// Add key, value to currently opened file
// REQUIRES: key is after any previously added key according to comparator.
Status Add(const Slice& user_key, const Slice& value);
// Finalize writing to sst file and close file.
//
// An optional ExternalSstFileInfo pointer can be passed to the function
// which will be populated with information about the created sst file
Status Finish(ExternalSstFileInfo* file_info = nullptr);
private:
class SstFileWriterPropertiesCollectorFactory;
class SstFileWriterPropertiesCollector;
struct Rep;
Rep* rep_;
};
} // namespace rocksdb