req:wcf service and asp.net 4.0 (slect,insert,delete,update) operations

let's start from dbml file(where we need to add the connections)
In dbml file we need to add connections from server explorer tables will be on left side and stored procedures will be on right hand side.


add the service Reference and any change in .svc file and on service client extensions please update service Reference.

In service file (.svc) we need to write all the functions required to execute for a given application

<OperationContract()> _
Public Function GetPublicHolidays(employeeID As String, StartDate As Date) As List(Of employees)
Dim db As New DataConnectivityDataContext
Dim q = (From e In db.employees Where e.employee_id = companyID e.holiday_date >= StartDate Select e).ToList
db.Dispose()
Return q

End Function

then in mainpage class call that function
please note:I am using async function so if you are using async function first install Async CTP 3.0 (for silvelight 4 and 5 )then add these two dll's
AsyncCTPLibrary_Silvelight.dll
AsyncCTPLibrary.dll

Private Async Function GetemplyeeData(employee_id As String, StDate As Date) As Task(Of ObservableCollection(Of projectname.ServiceReference1.employees))
Dim svc = New projectname.ServiceReference1.ShiftRosteringServiceClient()

Dim t1 = MyServiceClientExtensions.GetemployeeAsyncHelper(svc, employeeID, StDate)

Await t1
Dim s = t1.Result

Return s
End Function

in MyServiceClientExtensions add helper fuction like this:

Public Function GetEmployeeAsyncHelper(client As projectname.ServiceReference1.ShiftRosteringServiceClient, _
EmployeeID As String, StartDate As Date) As Task(Of ObservableCollection(Of projectname.ServiceReference1.employees))

Dim taskCompletion = New TaskCompletionSource(Of ObservableCollection(Of projectname.ServiceReference1.employees))()

AddHandler client.getemployeesCompleted, Sub(s, e)
If e.[Error] IsNot Nothing Then taskCompletion.TrySetException(e.[Error]) ElseIf e.Cancelled Then taskCompletion.TrySetCanceled() Else taskCompletion.TrySetResult(e.Result) End If
End Sub

client.getemployeeAsync(employeeID, StartDate)
Return taskCompletion.Task

End Function