How to fix create character?

[ByLeon]

i test source:

[DriftCityPacket(82, DriftCityServer.ServerType.Lobby)]
        public static void CreateCharacter(DriftCityPacket packet)
            {
            string characterName = packet.Reader.ReadUnicode();
            //string characterUID = packet.Reader.ReadUnicode();//test no read db problem.
            //string Avatar = packet.Reader.ReadUnicode();//test no read db problem.


            string characterUID = "1";//test
            string Avatar = "3";//test


            DbConnection dbconn_c = Database.GetConnection();
            DbCommand crechar = dbconn_c.CreateCommand();           
            crechar.CommandText = @"SET FOREIGN_KEY_CHECKS=0;Insert into characters (UID, Name, Avatar) values ('" + characterUID + "', '" + characterName + "', '" + Avatar + "')";
            crechar.ExecuteNonQuery();
            Log.WriteLine("Create Character Success Name: {0} UID: {1} Avatar: {2}", characterName, characterUID, Avatar);


            // TODO: Verify, Handle


            var ack = new DriftCityPacket(82);
            //var ack = new DriftCityPacket(83); //Create Character and go game
            ack.Writer.WriteUnicodeStatic(characterName, 21);
            ack.Writer.WriteUnicodeStatic(characterUID, 21);
            ack.Writer.WriteUnicodeStatic(Avatar, 21);
            packet.Sender.Send(ack);
            //packet.Sender.Error("Create New Character Error.");
            }