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// Copyright (c) 2011-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).
#include <cstdio>
#include <string>
#include <vector>
#include "rocksdb/db.h"
#include "rocksdb/options.h"
#include "rocksdb/slice.h"
#if defined(OS_WIN)
std::string kDBPath = "C:\\Windows\\TEMP\\rocksdb_column_families_example";
#else
std::string kDBPath = "/tmp/rocksdb_column_families_example";
#endif
using ROCKSDB_NAMESPACE::ColumnFamilyDescriptor;
using ROCKSDB_NAMESPACE::ColumnFamilyHandle;
using ROCKSDB_NAMESPACE::ColumnFamilyOptions;
using ROCKSDB_NAMESPACE::DB;
using ROCKSDB_NAMESPACE::DBOptions;
using ROCKSDB_NAMESPACE::Options;
using ROCKSDB_NAMESPACE::ReadOptions;
using ROCKSDB_NAMESPACE::Slice;
using ROCKSDB_NAMESPACE::Status;
using ROCKSDB_NAMESPACE::WriteBatch;
using ROCKSDB_NAMESPACE::WriteOptions;
int main() {
// open DB
Options options;
options.create_if_missing = true;
DB* db;
Status s = DB::Open(options, kDBPath, &db);
assert(s.ok());
// create column family
ColumnFamilyHandle* cf;
s = db->CreateColumnFamily(ColumnFamilyOptions(), "new_cf", &cf);
assert(s.ok());
// close DB
s = db->DestroyColumnFamilyHandle(cf);
assert(s.ok());
delete db;
// open DB with two column families
std::vector<ColumnFamilyDescriptor> column_families;
// have to open default column family
column_families.push_back(ColumnFamilyDescriptor(
ROCKSDB_NAMESPACE::kDefaultColumnFamilyName, ColumnFamilyOptions()));
// open the new one, too
column_families.push_back(
ColumnFamilyDescriptor("new_cf", ColumnFamilyOptions()));
std::vector<ColumnFamilyHandle*> handles;
s = DB::Open(DBOptions(), kDBPath, column_families, &handles, &db);
assert(s.ok());
// put and get from non-default column family
s = db->Put(WriteOptions(), handles[1], Slice("key"), Slice("value"));
assert(s.ok());
std::string value;
s = db->Get(ReadOptions(), handles[1], Slice("key"), &value);
assert(s.ok());
// atomic write
WriteBatch batch;
batch.Put(handles[0], Slice("key2"), Slice("value2"));
batch.Put(handles[1], Slice("key3"), Slice("value3"));
batch.Delete(handles[0], Slice("key"));
s = db->Write(WriteOptions(), &batch);
assert(s.ok());
// drop column family
s = db->DropColumnFamily(handles[1]);
assert(s.ok());
// close db
for (auto handle : handles) {
s = db->DestroyColumnFamilyHandle(handle);
assert(s.ok());
}
delete db;
return 0;
}
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