ADO.NET :: Linq To Sql Determine Which Tables To Write?
Sep 9, 2010
I was wondering how Linq to Sql determines which tables to write to when given primary/foreign Key relationships. I can (hopefully) better explain using an example. I have the following tables:
Customer CustomerStatus CustomerType CustomerAddresses
Therefore I have a Customer Entity, a CustomerStatus entity, a CustomerType Entity and a List of CustomerAddresses. In my code, I load up the Customer Entity and the List of CustomerAddresses because that's all I need. For some reason Linq to Sql is trying to insert a new Customer Status record. I have no idea why its doing this.
Can anyone please explain to me how linq to sql determines which table(s) will be written to based on the entities above?
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eg: thiss is the ordinary query
[Code]....
how in linq??
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[Code]....
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[Code]....
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[Code]....
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[Code]....
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[Code]....
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[Code]....
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I'm a newbie to this so bear with me. From what I've read online LINQ to Entity should see the relationships without having to specify the joins between multiple tables. I have a relationship that goes across 4 tables Employee, EmployeeDepartmentLink, EmployeeProjectLink, and Project. The idea is an employee can be in multiple departments and work on multiple projects with it being specified which department the employee is in for that project.
This is a C# MVC3 program connecting to a SQL database using VS 2010 Express.
I have no problem with running this query to find employees on a project:
[Code]....
Tring to do the reverse, finding projects that an employee worked on results in an error:
[Code]....
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