title: Most efficient way of reordering an array with a known order
body: <p>I have an array that is given to me in random order. The array is an array of arrays, and I am given an order to place the array in based on a key that exists in each sub-array. </p>
  
  <p>For example, I am given the array <code>array(array('id' =&gt; 1), array('id' =&gt; 2))</code>. I am told to order the arrays in the order (2,1) based upon the key 'id' of each sub-array.</p>
  
  <p>What is the most efficient way to do this in PHP?</p>