Gridview - SqlDatasource - How Do You Get All Values For A Like Text Parameter Or A Boolean Field When Filtering?

I have a gridview connected to a sqldatasource, and it works pretty good.  It gives me the subsets of the information that I need.  But, I really want to let them choose all the companies and/or any status.  What's the best way to get all the values in the gridview...besides removing the filters :)

I thought the company would be easy, I'd just set the selected value to blank "", and then it'd get them all....but that's not working.  And, for the boolean, I have no idea to get the value without having a separate query.

(tabs_done=@tabsdone) and (company like '%' + @company + '%')1 <asp:DropDownList ID="drpdwnProcessingStatus" runat="server">
2 <asp:ListItem Value="0">Open</asp:ListItem>
3 <asp:ListItem Value="1">Completed</asp:ListItem>
4 </asp:DropDownList>
5
6
7 <asp:DropDownList ID="drpdwnCompany" runat="server">
8 <asp:ListItem Value="">All</asp:ListItem>
9 <asp:ListItem Value="cur">Cur District</asp:ListItem>
10 <asp:ListItem Value="jho">Jho District</asp:ListItem>
11 <asp:ListItem Value="sea">Sea District</asp:ListItem>
12 <asp:ListItem Value="san">Net District</asp:ListItem>
13 <asp:ListItem Value="sr">Research District</asp:ListItem>
14 </asp:DropDownList>
15
16
17 <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:HRFormsConnectionString %>"
18 SelectCommand="SELECT DISTINCT [id], [lastname], [company] FROM [hr_term] hr where (tabs_done=@tabsdone) and (company like '%' + @company + '%')">
19 <SelectParameters>
20 <asp:ControlParameter ControlID="drpdwnProcessingStatus" DefaultValue="0" Name="tabsdone" PropertyName="SelectedValue" />
21 <asp:ControlParameter ControlID="drpdwnCompany" DefaultValue="" Name="company" PropertyName="SelectedValue" />
22 </SelectParameters>
23 </asp:SqlDataSource>
24