rocksdb/db/db_impl_readonly.h
Igor Canadi b06840aa7d [CF] Rethinking ColumnFamilyHandle and fix to dropping column families
Summary:
The change to the public behavior:
* When opening a DB or creating new column family client gets a ColumnFamilyHandle.
* As long as column family handle is alive, client can do whatever he wants with it, even drop it
* Dropped column family can still be read from (using the column family handle)
* Added a new call CloseColumnFamily(). Client has to close all column families that he has opened before deleting the DB
* As soon as column family is closed, any calls to DB using that column family handle will fail (also any outstanding calls)

Internally:
* Ref-counting ColumnFamilyData
* New thread-safety for ColumnFamilySet
* Dropped column families are now completely dropped and their memory cleaned-up

Test Plan: added some tests to column_family_test

Reviewers: dhruba, haobo, kailiu, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16101
2014-02-12 13:47:09 -08:00

104 lines
3.7 KiB
C++

// Copyright (c) 2013, 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.
//
// Copyright (c) 2012 Facebook. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#pragma once
#include "db/db_impl.h"
#include <deque>
#include <set>
#include <vector>
#include <string>
#include "db/dbformat.h"
#include "db/log_writer.h"
#include "db/snapshot.h"
#include "rocksdb/db.h"
#include "rocksdb/env.h"
#include "port/port.h"
#include "util/stats_logger.h"
namespace rocksdb {
class DBImplReadOnly : public DBImpl {
public:
DBImplReadOnly(const DBOptions& options, const std::string& dbname);
virtual ~DBImplReadOnly();
// Implementations of the DB interface
using DB::Get;
virtual Status Get(const ReadOptions& options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value);
// TODO: Implement ReadOnly MultiGet?
using DBImpl::NewIterator;
virtual Iterator* NewIterator(const ReadOptions&,
ColumnFamilyHandle* column_family);
virtual Status NewIterators(
const ReadOptions& options,
const std::vector<ColumnFamilyHandle*>& column_family,
std::vector<Iterator*>* iterators) {
// TODO
return Status::NotSupported("Not supported yet.");
}
using DBImpl::Put;
virtual Status Put(const WriteOptions& options,
ColumnFamilyHandle* column_family, const Slice& key,
const Slice& value) {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Merge;
virtual Status Merge(const WriteOptions& options,
ColumnFamilyHandle* column_family, const Slice& key,
const Slice& value) {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Delete;
virtual Status Delete(const WriteOptions& options,
ColumnFamilyHandle* column_family, const Slice& key) {
return Status::NotSupported("Not supported operation in read only mode.");
}
virtual Status Write(const WriteOptions& options, WriteBatch* updates) {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::CompactRange;
virtual Status CompactRange(ColumnFamilyHandle* column_family,
const Slice* begin, const Slice* end,
bool reduce_level = false,
int target_level = -1) {
return Status::NotSupported("Not supported operation in read only mode.");
}
virtual Status DisableFileDeletions() {
return Status::NotSupported("Not supported operation in read only mode.");
}
virtual Status EnableFileDeletions(bool force) {
return Status::NotSupported("Not supported operation in read only mode.");
}
virtual Status GetLiveFiles(std::vector<std::string>&,
uint64_t* manifest_file_size,
bool flush_memtable = true) {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Flush;
virtual Status Flush(const FlushOptions& options,
ColumnFamilyHandle* column_family) {
return Status::NotSupported("Not supported operation in read only mode.");
}
private:
friend class DB;
// No copying allowed
DBImplReadOnly(const DBImplReadOnly&);
void operator=(const DBImplReadOnly&);
};
}