package mainimport ("bytes""fmt""io/ioutil""os". "github.com/szferi/gomdb"
)// Most mdb functions/methods can return errors. This example ignores errors
// for brevity. Real code should check all return values.
func main() {// create a directory to hold the databasepath, _ := ioutil.TempDir("", "mdb_test")defer os.RemoveAll(path)// open the dbenv, _ := NewEnv()env.SetMapSize(1 << 20) // max file sizeenv.Open(path, 0, 0664)defer env.Close()txn, _ := env.BeginTxn(nil, 0)dbi, _ := txn.DBIOpen(nil, 0)defer env.DBIClose(dbi)txn.Commit()// write some datatxn, _ = env.BeginTxn(nil, 0)num_entries := 10for i := 0; i < num_entries; i++ {key := fmt.Sprintf("Key-%d", i)val := fmt.Sprintf("Val-%d", i)txn.Put(dbi, []byte(key), []byte(val), 0)}txn.Commit()// inspect the databasestat, _ := env.Stat()fmt.Println(stat.Entries)// scan the databasetxn, _ = env.BeginTxn(nil, RDONLY)defer txn.Abort()cursor, _ := txn.CursorOpen(dbi)defer cursor.Close()for {bkey, bval, err := cursor.Get(nil, nil, NEXT)if err == NotFound {break}if err != nil {panic(err)}fmt.Printf("%s: %s\n", bkey, bval)}// random accessbval, _ := txn.Get(dbi, []byte("Key-3"))fmt.Println(string(bval))fmt.Printf("*********range begin*********\n")bkey := []byte("Key-2")bkeyEnd := []byte("Key-5")// var MDB_SET_RANGE uint = 17// var op = MDB_SET_RANGE    var op uint = SET_RANGEfor {bkey, bval, err := cursor.Get(bkey, nil, op)if err == NotFound || bytes.Compare(bkey, bkeyEnd) > 0 {break}if err != nil {panic(err)}fmt.Printf("%s: %s\n", bkey, bval)op = NEXT}fmt.Printf("**********range end********\n")
}