<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT DISTINCT [idOficina], [nome], [contacto], [morada], [cidade], (SELECT CONVERT(DECIMAL(10,1),convert(float,SUM(avaliacao))/convert(float,COUNT(idOficinaFK))) FROM Avaliacoes WHERE idOficinaFK=@idOficina) as avaliacao FROM Oficinas, Avaliacoes WHERE idOficina=@idOficina">
                               <SelectParameters>
                                   <asp:QueryStringParameter Name="idOficina" querystringfield="idoficina"  />
                               </SelectParameters>
                           </asp:SqlDataSource>

                           <asp:GridView ID="GridView1" runat="server" Class="table col-md-6 col-lg-6 col-sm-6" AutoGenerateColumns="False" DataSourceID="SqlDataSource2">
                               <Columns>
                                   <asp:BoundField DataField="avaliacao" HeaderText="avaliacao" SortExpression="avaliacao" />
                                   <asp:BoundField DataField="comentario" HeaderText="comentario" SortExpression="comentario" />
                               </Columns>

                           </asp:GridView>

                           <asp:SqlDataSource ID="SqlDataSource2" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT [avaliacao], [comentario] FROM [Avaliacoes] WHERE ([comentario] IS NOT NULL AND idOficinaFK=@idOficina) ORDER BY [avaliacao] DESC">
                               <SelectParameters>
                                   <asp:QueryStringParameter Name="idOficina" querystringfield="idoficina"  />
                               </SelectParameters>
                           </asp:SqlDataSource>