lmdb-safe/examples/basic.cc

45 lines
1.1 KiB
C++

#include "../lmdb-safe.hh"
#include <iostream>
using namespace std;
using namespace LMDBSafe;
void checkLMDB(MDBEnv *env, MDBDbi dbi)
{
auto rotxn = env->getROTransaction();
MDBOutVal data;
if (!rotxn->get(dbi, "lmdb", data)) {
cout << "Outside RW transaction, found that lmdb = " << data.get<string_view>() << endl;
} else
cout << "Outside RW transaction, found nothing" << endl;
}
int main()
{
auto env = getMDBEnv("./basic.lmdb", MDB_NOSUBDIR, 0600);
auto dbi = env->openDB("example", MDB_CREATE);
auto txn = env->getRWTransaction();
mdb_drop(*txn, dbi, 0);
txn->put(dbi, "lmdb", "great");
MDBOutVal data;
if (!txn->get(dbi, "lmdb", data)) {
cout << "Within RW transaction, found that lmdb = " << data.get<string_view>() << endl;
} else
cout << "Found nothing" << endl;
std::thread elsewhere(checkLMDB, env.get(), dbi);
elsewhere.join();
txn->commit();
cout << "Committed data" << endl;
checkLMDB(env.get(), dbi);
txn = env->getRWTransaction();
mdb_drop(*txn, dbi, 0);
txn->commit();
}