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// Copyright 2012 The LevelDB-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This program creates a leveldb db at /tmp/db.
//
// To build and run:
// g++ make-db.cc -lleveldb && ./a.out
#include <iostream>
#include "leveldb/db.h"
static const char* dbname = "/tmp/db";
// The program consists of up to 4 stages. If stage is in the range [1, 4],
// the program will exit after the stage'th stage.
// 1. create an empty DB.
// 2. add some key/value pairs.
// 3. close and re-open the DB, which forces a compaction.
// 4. add some more key/value pairs.
static const int stage = 4;
int main(int argc, char** argv) {
leveldb::Status status;
leveldb::Options o;
leveldb::WriteOptions wo;
leveldb::DB* db;
o.create_if_missing = true;
o.error_if_exists = true;
if (stage < 1) {
return 0;
}
std::cout << "Stage 1" << std::endl;
status = leveldb::DB::Open(o, dbname, &db);
if (!status.ok()) {
std::cerr << "DB::Open " << status.ToString() << std::endl;
return 1;
}
if (stage < 2) {
return 0;
}
std::cout << "Stage 2" << std::endl;
status = db->Put(wo, "foo", "one");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Put(wo, "bar", "two");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Put(wo, "baz", "three");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Put(wo, "foo", "four");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Delete(wo, "bar");
if (!status.ok()) {
std::cerr << "DB::Delete " << status.ToString() << std::endl;
return 1;
}
if (stage < 3) {
return 0;
}
std::cout << "Stage 3" << std::endl;
delete db;
db = NULL;
o.create_if_missing = false;
o.error_if_exists = false;
status = leveldb::DB::Open(o, dbname, &db);
if (!status.ok()) {
std::cerr << "DB::Open " << status.ToString() << std::endl;
return 1;
}
if (stage < 4) {
return 0;
}
std::cout << "Stage 4" << std::endl;
status = db->Put(wo, "foo", "five");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Put(wo, "quux", "six");
if (!status.ok()) {
std::cerr << "DB::Put " << status.ToString() << std::endl;
return 1;
}
status = db->Delete(wo, "baz");
if (!status.ok()) {
std::cerr << "DB::Delete " << status.ToString() << std::endl;
return 1;
}
return 0;
}
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