急！请大家帮帮忙！

原程序：
 if (!this.IsPostBack)
        {
            SqlConnection strcon = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["strcon"]);
            strcon.Open();
            SqlDataAdapter sda = new SqlDataAdapter("select * from delivery where user_id=" + Request.QueryString["user_id"], strcon);
            DataSet ds = new DataSet();
            sda.Fill(ds, "delivery");
            DataRowView rowview = ds.Tables["delivery"].DefaultView[0];
            Label1.Text = rowview["documents"].ToString();
            Label2.Text = rowview["documents_name"].ToString();

            ds.Clear();
            strcon.Close();
        }
错误提示：‘=’号附近有错误
这是怎么回事啊？