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/* This is free and unencumbered software released into the public domain. */
#include <cstdio>
#include <cstdlib>
#include <lmdb++.h>
int main() {
/* Create and open the LMDB environment: */
auto env = lmdb::env::create();
env.set_mapsize(1UL * 1024UL * 1024UL * 1024UL); /* 1 GiB */
env.open("./example.mdb", 0, 0664);
/* Insert some key/value pairs in a write transaction: */
auto wtxn = lmdb::txn::begin(env);
auto dbi = lmdb::dbi::open(wtxn, nullptr);
dbi.put(wtxn, "username", "jhacker");
dbi.put(wtxn, "email", "jhacker@example.org");
dbi.put(wtxn, "fullname", "J. Random Hacker");
wtxn.commit();
/* Fetch key/value pairs in a read-only transaction: */
auto rtxn = lmdb::txn::begin(env, nullptr, MDB_RDONLY);
auto cursor = lmdb::cursor::open(rtxn, dbi);
std::string key, value;
while (cursor.get(key, value, MDB_NEXT)) {
std::printf("key: '%s', value: '%s'\n", key.c_str(), value.c_str());
}
cursor.close();
rtxn.abort();
/* The enviroment is closed automatically. */
return EXIT_SUCCESS;
}
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