title: in entity framework how to have a stored procedure return nullable when column is defined as not nullable?
body: <p>In SQL server I have a table with a column defined as not nullable.</p>
  
  <p>And I have a stored procedure doing some joins so that the resulting output column for that field is actually never null.</p>
  
  <p>In EF5 I have a complex type for that output which was automatically generated by EF (when I added the stored procedure to the model) and the field was generated as "nullable = false" I guess because the definition for that column in all the joined tables is "NOT NULL".</p>
  
  <p>Now, in my solution I query the db with the store procedure and do a union (just for display, no "Savechanges") where the table I union with has NULL for that column/field in some rows;  and there is where I am in trouble because I get an exception saying null is not allowed by my complex type.</p>
  
  <p>My solution so far has been to manually change from not nullable to nullable the type of the complex type field, but every time I update from the model I get my change reverted (of course).</p>
  
  <p>I guess there's a smarter solution but I can't see it...</p>
  
  <p>Any idea?</p>