Bug: Datatable-bound Gridviews stuck in Read-Only when there is a UNION in the query

[Philippe]

Hello

I created a new form, added a RadGridView to it, and populated it using a query containing a UNION statement.

pGrid.BeginUpdate();
// QueryDB below returns a Datatable with the resultset or the SELECT
DataTable rs = clsDBConn.QueryDB("SELECT a,b,c FROM T1 UNION SELECT a,b,c FROM T2");
pGrid.DataSource = null;
pGrid.DataSource = rs;
pGrid.MasterTemplate.AutoGenerateColumns = true;
pGrid.MasterTemplate.AllowAutoSizeColumns = true;
pGrid.MasterTemplate.AllowAddNewRow = false;
pGrid.MasterTemplate.AllowDeleteRow = false;
pGrid.MasterTemplate.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.None;
pGrid.MasterTemplate.SelectionMode = GridViewSelectionMode.FullRowSelect;
pGrid.TableElement.ShowTranslucentSelectionRectangle = true;
pGrid.ShowRowHeaderColumn = false;
pGrid.EndUpdate();

foreach (GridViewDataColumn column in pGrid.Columns)
{
    column.ReadOnly = false;
}

Even with the ReadOnly=false, when I changed a cell's value and clicked elsewhere, a "Data Exception" message saying "Column 'a' is read only." poped up. I put my UNION statement in a view, called the view, and everything worked as expected.

[Julian Benkov]

Hello Philippe,

Please check the generated DataTable Columns' ReadOnly property. In this situation the generated Columns of the DataTable can be in ReadOnly mode.

foreach(DataColumn column in dataTable.Columns)
{
    if(column.ReadOnly)
    {
        Console.WriteLine("Column: {0} is readonly.", column.ColumnName);
    }
}

I hope this helps. Let me know if you need further assistance.

Regards,
Julian Benkov
the Telerik team

[Philippe]

It is indeed the DataTable's column itself that is Read only. Seems my current workaround of converting the statement to a view is a proper solution then.

Thanks Julian.