title: performance PHP select where vs left join
body: <p>I work for multilangual book library cms. For DBs design i have two idea : </p>
  
  <p>One :</p>
  
  <pre><code>id | title | desc | date | writer | publisher | lang | more more | ...
  </code></pre>
  
  <p>for result:</p>
  
  <p><code>result = SELECT blah1, blah2, foreign_key FROM foo WHERE key=bar AND lang = en</code></p>
  
  <p>Two: add another table for language :</p>
  
  <pre><code>id | book_id | lang 
  </code></pre>
  
  <p>for result work with PHP <code>LEFT JOIN</code> methods.</p>
  
  <p>which way is better and faster for big database ?!</p>
  
  <p>NOTE:<code>I have 27 columns in my table and 4500 books.</code></p>