c# oracle 数据库连接以及参数化查询

private  string OracleSearchDemo(string cadqueueId)
{
    string address = null;
    using (OracleConnection cn = GetOraConnection())
    {
        string sqlGetAddress = "Select SvjDataAddress From Cadqueue Where CadqueueId = :CadqueueId";
        OracleCommand cmd = new OracleCommand(sqlGetAddress, cn);
        cmd.CommandType = CommandType.Text;
        cmd.Parameters.Add(new OracleParameter("CadqueueId", cadqueueId));
        cn.Open();

        OracleDataReader dtr = cmd.ExecuteReader();
        if (dtr.Read())
        {
            address = dtr["SvjDataAddress"].ToString();
            // 修改数据
            // string sqlChangeStatus = "update cadqueue q  set q.status = :status  Where CadqueueId = :CadqueueId";
            // cmd.CommandText = sqlChangeStatus;
            // cmd.Parameters.Clear();
            // cmd.Parameters.Add("CadqueueId", cadqueueId);
            // cmd.ExecuteNonQuery();
        }
        dtr.Close();
        cn.Close();
    }
    return address;
}

private OracleConnection GetOracleConnection()
{
    OracleConnection conn = new OracleConnection(); // connectString 最好通过 app.config 配置
    conn.ConnectionString = "Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=***.***.***.***)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=***)));Persist Security Info=True;User ID=***;Password=***;" ;
    return conn;
}