SQLDatasource Select Parameter causes time out

Question

If I run this code, the result is returned in less than a second -

<asp:SqlDataSource ID="OrdersSqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:OperationsPortal.Properties.Settings.JDEProd %>" SelectCommand="
                SELECT A.Test
                FROM PRODDTA.F5547510 AS B WITH(NOLOCK)
                INNER JOIN PRODDTA.F4211 AS A WITH(NOLOCK) ON B.SCDOCO = A.SDDOCO
                INNER JOIN PRODDTA.F0101 C WITH(NOLOCK) ON A.SDAN8 = C.ABAN8
                **WHERE (A.SDMCU = '         CHP')**
                ORDER BY ORDERDATE">
                <SelectParameters>
                    <asp:ControlParameter ControlID="drpBranch" DefaultValue="CHP" Name="BranchPlant" PropertyName="SelectedValue" />
                </SelectParameters>
            </asp:SqlDataSource>

However, as soon as I change the WHERE statement to use a Select Parameter, the query times out -

<asp:SqlDataSource ID="OrdersSqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:OperationsPortal.Properties.Settings.JDEProd %>" SelectCommand="
                SELECT A.Test                      
                FROM PRODDTA.F5547510 AS B WITH(NOLOCK)
                INNER JOIN PRODDTA.F4211 AS A WITH(NOLOCK) ON B.SCDOCO = A.SDDOCO
                INNER JOIN PRODDTA.F0101 C WITH(NOLOCK) ON A.SDAN8 = C.ABAN8
                **WHERE (A.SDMCU = '         ' + @BranchPlant)**
                ORDER BY ORDERDATE">
                <SelectParameters>
                    <asp:ControlParameter ControlID="drpBranch" DefaultValue="CHP" Name="BranchPlant" PropertyName="SelectedValue" />
                </SelectParameters>
            </asp:SqlDataSource>

Does anyone know what I can do to fix this? I get similar results if I run this in Management Studio, but in Management Studio I can add "OPTION(RECOMPILE)" to the end of the query and that fixes the issue. But, that doesn't seem to work in my SQLDatatSource SelectCommand.

Answer 1

In case someone else runs into this issue, this is how I ended up fixing the performance issue. I declared a variable up top, set the value of the variable to the Select Parameter and used OPTION (OPTIMIZE) -

<asp:SqlDataSource CancelSelectOnNullParameter="False"  ID="OrdersSqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:OperationsPortal.Properties.Settings.JDEProd %>" SelectCommand="
                DECLARE @Branch varchar(12)
                SET @Branch = @BranchPlant
                SELECT A.Test
                FROM PRODDTA.F5547510 AS B WITH(NOLOCK)
                INNER JOIN PRODDTA.F4211 AS A WITH(NOLOCK) ON (A.SDDOCO = B.SCDOCO AND A.SDLNID = B.SCLNID)
                INNER JOIN PRODDTA.F0101 C WITH(NOLOCK) ON A.SDSHAN = C.ABAN8
                WHERE (A.SDMCU = '         ' + @Branch) 
                OPTION (OPTIMIZE FOR (@Branch = 'CHP'))">
                <SelectParameters>
                    <asp:ControlParameter ControlID="drpBranch" Name="BranchPlant" PropertyName="SelectedValue" Type="String" />
                </SelectParameters>
            </asp:SqlDataSource>