title: Can an ActiveRecord `.select` method have an interpolated string like in `.where`?
body: <p>ActiveRecord's <code>.where()</code> query method supports interpolation like this:</p>
  
  <pre><code>Book.where("author_id IS ? AND genre_id IS ?", author_id, genre_id)
  </code></pre>
  
  <p>Does the <code>.select()</code> method support similar interpolation, or would we need to use standard Ruby string interpolation (e.g. <code>"WHEN genre_id IS #{genre_id} THEN 2"</code>).</p>
  
  <p>(This might seem like a far-fetched use case, but essentially we're building a query with a calculated field - <code>SUM() as sum</code> for example - which uses different values depending on each record's fields, via a <code>CASE</code> statement, and we'd like to avoid hard-coding values into the query.)</p>
  
  <p>I'm interested in all answers, but this particular application happens to still be on Rails 3.2.x.</p>