updating a dataset

[steve_rm]

Hello,

When l got to update my database l get this error message "Missing the datacolumn 'DepartmentName' in the DataTable 'Employee' for the sourceColumn 'DepartmentName' ".

I have a database application. 2 tables. Department and Employee.
Department -> DepartmentCode (PK)
DepartmentName

Employee -> EmployeeID (PK)
Name
Surname
DepartmentCode (FK)

I have create this relationship in code using relationships in the form load event. see below:

private void frmEmployees_Load(object sender, System.EventArgs e)
		{
			try
			{
				cnn.Open();
				//Fill the DataSet with the Employee details
				OleDbCommand cmd = cnn.CreateCommand();
				cmd.CommandType = CommandType.Text;
				cmd.CommandText = "SELECT * FROM Employee";
				da.SelectCommand = cmd;
				//Gets all the details for the database, e.g. Primary keys
				da.FillSchema(ds,SchemaType.Source,"Employee");
				da.Fill(ds,"Employee");
				
				//Fill the DataSet wtih the Department details
				cmd.CommandText = "SELECT * FROM Department";
				da.SelectCommand = cmd;
				da.FillSchema(ds,SchemaType.Source,"Department");
				da.Fill(ds,"Department");
				
				//Assign the parent column of the Department table and child column of the
				//employee table. Remember - DepartmentCode PK in Department table, and 
				//FK in the Employee Table.
				DataColumn parentColumn = ds.Tables["Department"].Columns["DepartmentCode"];
				DataColumn childColumn = ds.Tables["Employee"].Columns["DepartmentCode"];
				
				//Clear the relation of any data. Not really nessessary as we are creating from new.
				//However, if we are to reuse then we must clear all contents.
				ds.Relations.Clear();
				drEmployees = new DataRelation("EmployeeDetails",parentColumn,childColumn);
				ds.Relations.Add(drEmployees);
				
				//Display the details of the first employee in the database.
				txtEmployeeID.Text = ds.Tables["Employee"].Rows[0]["EmployeeNumber"].ToString();
				txtFirstName.Text = ds.Tables["Employee"].Rows[0]["FirstName"].ToString();
				txtSurname.Text = ds.Tables["Employee"].Rows[0]["Surname"].ToString();
				txtDateOfBirth.Text = ds.Tables["Employee"].Rows[0]["DateOfBirth"].ToString();
				txtAddress1.Text = ds.Tables["Employee"].Rows[0]["Address1"].ToString();
				txtAddress2.Text = ds.Tables["Employee"].Rows[0]["Address2"].ToString();
				cboDepartment.Text = ds.Tables["Employee"].Rows[0]["DepartmentCode"].ToString();

				string departmentCode = ds.Tables["Employee"].Rows[0]["DepartmentCode"].ToString();
				DataRow[] departmentRow = ds.Tables["Department"].Select("DepartmentCode = '" + departmentCode + "' ");
				string departmentName = departmentRow[0]["DepartmentName"].ToString();
				
				
				this.UpdateDepartments();//Call to display combo box information
			}	
			catch ( OleDbException ex )
			{
				MessageBox.Show(ex.Message);
			}
			catch ( Exception ex )
			{
				MessageBox.Show(ex.Message);
			}
		}

When l click the update button, l run this code and get an error on the update.

ds.Tables["Employee"].Rows[0]["FirstName"] = txtFirstName.Text;
ds.Tables["Employee"].Rows[0]["Surname"] = txtSurname.Text;
ds.Tables["Employee"].Rows[0]["DepartmentCode"] = departmentCode;

da.Update(ds,"Employee"); //Error ocurrs here

I hope someone can help me with this question. very important.

Thanks in advance,

Steve