SqlDataSource-caching

                                   runat="server"
                           ProviderName="System.Data.SqlClient"
                           ConnectionString="<%$ ConnectionStrings:Northwind %>"
                           SelectCommand="SELECT DISTINCT City FROM Employees"
                           EnableCaching="True"
                           CacheDuration="3600">

                                  runat="server"
                          DataSourceID="sourceEmployeeCities"
                          DataTextField="City"
                          Width="205px"
                          AutoPostBack="True">


                                   runat="server"
                           ProviderName="System.Data.SqlClient"
                           ConnectionString="<%$ ConnectionStrings:Northwind %>"
                           SelectCommand="SELECT EmployeeID, FirstName, LastName, Title, City FROM Employees WHERE City=@City"
                           EnableCaching="True"
                           CacheDuration="600">




                              runat="server"
                      DataSourceID="sourceEmployees"
                      AutoGenerateColumns="False"
                      DataKeyNames="EmployeeID">


                                    ReadOnly="True" SortExpression="EmployeeID" />

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