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PORemoving Entities from Database table via Navigation Property using RIA Services and Entity Framework
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  1. PORemoving Entities from Database table via Navigation Property using RIA Services and Entity Framework
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    copied!<p>I have 3 normalised tables consisting of Employees, Departments and EmployeesToDepartments. I wish to be able to assign an Employee to one or more Department, hence the link table (EmployeesToDepartments). I can successfully query the database and extract the full hierarchy of entities via the Navigation properties using</p> <pre><code>this.ObjectContext.Employees.Include("EmployeesToDepartments").Include("EmployeesToDepartments.Department") </code></pre> <p>plus the [Include] attribute in the metadata, thus allowing me to access the Departments for a given Employee. Upon trying to remove a link between an [Employee] and [Department] in the [EmployeesToDepartments] table I was given a Foreign Key Constrain error.</p> <p>I have simplified my model to include just one navigation property between [Employees] and [EmployeesToDepartments]. A Foreign Key constraint between[Employees].[ID] and [EmployeesToDepartments].[IDEmployee] was preventing me from updating the EmployeesToDepartments table. With this removed via a Relationship setting I can now update the table. I can now execute the following code</p> <pre><code>foreach (var rel in _employee.EmployeesToDepartments) { _employee.EmployeesToDepartments.Remove(rel); } _domainContext.SubmitChanges(); </code></pre> <p>without error.</p> <p>I was expecting to see the entries in the RelEmployeesToDepartments with the IDEmployee to have been deleted. What I see in the table are the value 0 where the IDEmployee previously was.</p> <p>Is it possible to force a DELETE statement to be issued? Am I misunderstanding the basic concepts here?</p> <p>Any help would be much appreciated.</p>
 

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