error while submitting update query

greets all..

i have a table like this.

http://i48.tinypic.com/vdd1qa.png

and i want to show its footer value to a new table

which is like this

sl.no Total mat_total sci_total com_total

1 total1 700 1000 1050

and i used this source

OleDbConnection con;
    OleDbCommand com;
    string str;
    protected void Page_Load(object sender, EventArgs e)
    {
        string connstr = "provider=microsoft.ace.oledb.12.0;data source=c:\\users\\jammy\\documents\\visual studio 2010\\websites\\testing\\app_data\\test.accdb;persist security info=true";
        OleDbConnection conn = new OleDbConnection();
        conn.ConnectionString = connstr;

        OleDbDataAdapter adapter = new OleDbDataAdapter();
        adapter.UpdateCommand = new OleDbCommand();

        adapter.UpdateCommand.CommandText = "UPDATE table2 SET mat_total= SUM(maths) FROM Table1 WHERE ID=1";
        conn.Open();
        adapter.UpdateCommand.Connection = conn;
        adapter.UpdateCommand.ExecuteNonQuery();

    }

But the error i am facing is

Exception Details: System.Data.OleDb.OleDbException: Operation must use an updateable query