rocksdb/examples/c_simple_example.c

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

#include "rocksdb/c.h"

#include <unistd.h>	// sysconf() - get CPU count

const char DBPath[] = "/tmp/rocksdb_simple_example";

int main(int argc, char **argv) {
	rocksdb_t *db;
	rocksdb_options_t *options = rocksdb_options_create();
	// Optimize RocksDB. This is the easiest way to
	// get RocksDB to perform well
	long cpus = sysconf(_SC_NPROCESSORS_ONLN);	// get # of online cores
	rocksdb_options_increase_parallelism(options, (int)(cpus));
	rocksdb_options_optimize_level_style_compaction(options, 0);
	// create the DB if it's not already present
	rocksdb_options_set_create_if_missing(options, 1);

	// open DB
	char *err = NULL;
	db = rocksdb_open(options, DBPath, &err);
	assert(!err);

	// Put key-value
	rocksdb_writeoptions_t *writeoptions = rocksdb_writeoptions_create();
	const char key[] = "key";
	const char *value = "value";
	rocksdb_put(db, writeoptions, key, strlen (key), value,	\
			strlen (value) + 1, &err);
	assert(!err);
	// Get value
	rocksdb_readoptions_t *readoptions = rocksdb_readoptions_create();
	size_t len;
	value = rocksdb_get(db, readoptions, key, strlen (key), &len, &err);
	assert(!err);
	assert(strcmp(value, "value") == 0);

	// cleanup
	rocksdb_writeoptions_destroy(writeoptions);
	rocksdb_readoptions_destroy(readoptions);
	rocksdb_options_destroy(options);
	rocksdb_close(db);

	return 0;
}