title: Use int Id for a bigint column in EF6
body: <p>We're using Entity Framework 6 to build a data layer on top of a legacy Sql Server database that has Id columns of type <code>bigint</code>.  We want to use <code>int</code> for our Id column types rather than <code>long</code>, and we're confident that the tables will never grow beyond the size limit of an <code>int</code>.</p>
  
  <p>However, we're getting the following error:</p>
  
  <blockquote>
    <p>The specified cast from a materialized 'System.Int64' type to the
    'System.Int32' type is not valid.</p>
  </blockquote>
  
  <p>How can we achieve what we want without modifying the db column type?</p>