Ячейка datagridview как ссылка

void __table_ColumnChanged(object sender, DataColumnChangeEventArgs e)
{
if(e.Column.ColumnName != "a") return;
string code = e.Row["a"].ToString();
// где то заполненная справочная таблица sourceDataTable
DataRow[] sel_row = sourceDataTable.Select(string.format("id = {0}", code));
e.Row["b"] = sel_row[0]["b"];
e.Row["с"] = sel_row[0]["с"];
и т. д.
}

    private DataTable GetData(string sqlCommand)
    {
        string connectionString = "Integrated Security=SSPI;" +
            "Persist Security Info=False;" +
            "Initial Catalog=Northwind;Data Source=localhost";
 
        SqlConnection northwindConnection = new SqlConnection(connectionString);
 
        SqlCommand command = new SqlCommand(sqlCommand, northwindConnection);
        SqlDataAdapter adapter = new SqlDataAdapter();
        adapter.SelectCommand = command;
 
        DataTable table = new DataTable();
        table.Locale = System.Globalization.CultureInfo.InvariantCulture;
        adapter.Fill(table);
 
        return table;
    }