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System.Linq.IQueryable (interface)

System.Linq.IQueryable implements System.Collections.IEnumerable.
A subset of the standard query operators operate on objects that implement IQueryable<T> (the other subset operates on System.Collections.Generic.IEnumerable<T>).
Matt Warren writes:
… IQueryable no longer looks all that interesting; the good stuff has been pushed off into the new interface IQueryProvider.

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