lock object in one mthod and no lock in another method

public int ExecuteNoQuery(string sqlquery, Hashtable htData) {
try {
 lock(Myservice.dbcon)  
  {
    using (OracleCommand dbCommand = new OracleCommand(sqlquery, Myservice.dbcon)) 
        {
              int rowCount = dbCommand.ExecuteNonQuery();
              return 1;
        }
  }
}

public OracleDataReader Query(string sqlquery, Hashtable htData)
    {
        try
        {
            OracleDataReader dbReader = null;
            Random ran = new Random();
            int randomnumber = ran.Next(1,5);
           Myservice.dbcon = (OracleConnection) Myservice.htdbcon
           ["Connection_" +randomnumber];
            if (Myservice.dbcon.State != System.Data.ConnectionState.Executing 
              || Myservice.dbcon !=  System.Data.ConnectionState.Fetching)
                {
                    using (OracleCommand dbCommand = new OracleCommand(sqlquery,
                     Myservice.dbcon))
                    { 
                        dbReader = dbCommand.ExecuteReader();
                    }
                }
                return dbReader;
        }