Left Join in Subsonic3

I'm new in subsonic3, and I'm getting some errors when I try to use LeftJoin

    var q =

    from c in categories

    join p in products on c equals p.Category into ps

    from p in ps.DefaultIfEmpty()

    select new { Category = c, ProductName = p == null ? "(No products)" : p.ProductName };

The error is "System.Collections.G开发者_如何转开发eneric.Enumerable '...' cannot be used for parameter of type System.Linq.IQueryable

Does anyone had this error before? Did you fix it? Thanks

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I don't know which one is the IQueryable property but you probably know, just add the .AsEnumerable() method.

categories.AsEnumerable() or products.AsEnumerable()

I cant remember if you had to add the toList() method also but you can try it out.

categories.AsEnumerable().toList() or products.AsEnumerable().toList()