oledbdataadapter

I keep getting an InvalidOperationException ("Update requires a valid UpdateCommand when passed DataRow collection with modified rows"). I just cant work out what's wrong with the update command. Here's the code I have so far: OleDbConnection connection; OleDbDataAdapter clientsAdapter new OleDbDataAdapter(); DataSet myDataSet = new DataSet(); public void Setup() { connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=Clients.xlsx;Extended Properties=""Excel 12.0 Xml;HDR=YES"";"; connection = new OleDbConnection(connectionString); connection.Open(); // SQL clientsAdapter

I have got an Excel file in this form : Column 1 Column 2 Column 3 data1 data2 data1 data2 data1 data2 data1 data2 data1 data2 data3 That is, the whole Column 3 is empty except for the last row. I am accessing the Excel file via OleDbDataAdapter, returning a DataTable: here's the code. query = "SELECT * FROM [" + query + "]"; objDT = new DataTable(); objCmdSQL = this.GetCommand(); objCmdSQL.CommandText = query; objSQLDad = new OleDbDataAdapter(objCmdSQL); objSQLDad.Fill(objDT); return objDT; The point is, in this scenario my code returns a DataTable with just Column 1 and Column 2. My guess is

i try to get some Data from a Access Database via OleDB in a DataSet . But the DataSet is empty after the Fill() method. The same statement works and return 1 row when i trigger them manually in D*. OleDbConnection connection = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=Inventar.accdb"); DataSet1 DS = new DataSet1(); connection.Open(); OleDbDataAdapter DBAdapter = new OleDbDataAdapter( @"SELECT tbl_Computer.*, tbl_Besitzer.* FROM tbl_Computer INNER JOIN tbl_Besitzer ON tbl_Computer.FK_Benutzer = tbl_Besitzer.ID WHERE (((tbl_Besitzer.Vorname)='ma'));", connection);