rocksdb C example

main.c

/*
 * compiled with:
 * g++ -std=c++11 main.c -Wall -lrocksdb -lbz2 -lpthread -lsnappy -lz
 */

#include <rocksdb/c.h>

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
	rocksdb_t *db;
	rocksdb_options_t *opts;
	char *err = NULL;

	opts = rocksdb_options_create();

	// Optimize RocksDB. This is the easiest way to get RocksDB to perform well
	rocksdb_options_increase_parallelism(opts, 0);
	rocksdb_options_optimize_level_style_compaction(opts, 0);

	// create the DB if it's not already present
	rocksdb_options_set_create_if_missing(opts, 1);

	// open the db
	db = rocksdb_open(opts, "test.db", &err);
	if (err != NULL) {
		fprintf(stderr, "open database %s\n", err);
		exit(1);
	}

	free(err);
	err = NULL;

	rocksdb_writeoptions_t *writeopts = rocksdb_writeoptions_create();

	// put a new or existing key
	rocksdb_put(db, writeopts, "name", 4, "Koye", 4, &err);
	if (err != NULL) {
		fprintf(stderr, "put key %s\n", err);
		exit(1);
	}

	free(err);
	err = NULL;

	rocksdb_readoptions_t *readopts = rocksdb_readoptions_create();

	size_t rlen;
	// read the key back out
	char *value = rocksdb_get(db, readopts, "name", 4, &rlen, &err);
	if (err != NULL) {
		fprintf(stderr, "get key %s\n", err);
		exit(1);
	}

	free(err);
	err = NULL;

	printf("get key len: %lu value: \"%s\"\n", rlen, value);

	rocksdb_close(db);

	return 0;
}