Using Enum in where clause on projected type.

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I'm storing enum values in the database (postgres) as string types.  When I 
project the DbLinq classes into my business classes I parse the string values 
back into its original enum value.  It looks like this:

// DbLinq class:
public class DbLinq
{
  long ID { get; set; }
  string MyEnumVal { get; set; }
}

// Biz classes:
public enum MyEnumValue { One, Two }

public class MyClass
{
  long Id { get; set; }
  MyEnumValue MyEnumVal { get; set; }
}

// Projection code:
public IQueryable<MyClass> GetAll()
{
  using (var context = GetDbLinqContext())
  {
    return
      from r in context.Table
      select new MyClass
      {
        Id = r.ID,
        MyEnumVal = (MyEnumValue)Enum.Parse(typeof(MyEnumValue), r.MyEnumVal),
      }
  }
}

Now this works just fine if I simply loop over the items returned from 
GetAll(), but things blow up if I want to filter the items.  I.e. 
GetAll().Where(i => i.MyEnumVal == MyEnumValue.One)

I realize when this is included in the where clause it must send the parsing 
logic to the postgres server and could be very complicated, but I figured I go 
ahead and check.

Any ideas?

Original issue reported on code.google.com by abe.gill...@gmail.com on 29 Nov 2010 at 4:27