Strange array_diff results
<p>I'm getting some data from various db tables using codeigniter. Funny thing is that 10 lines above this code I was testing the concept with some other arrays which had names and everything worked as expected. Now that I'm trying the same thing with the data from my db it doesn't seem to be working.</p>

<p><strong>Code</strong></p>

<pre><code>            echo "a:";print_r($CITB);
            echo "&lt;br /&gt;b:";print_r($PRB);
            echo "&lt;br /&gt;c:";print_r($TB);
            echo "&lt;br /&gt;d:";print_r($TRB);


            $a = $CITB; //I know this is empty
            $b = array_diff($PRB,$a);
            $c = array_diff($TB, $b, $a);
            $d = array_diff($TRB, $c, $b, $a);

             echo "&lt;br /&gt;&lt;br /&gt;a:";print_r($a);
             echo "&lt;br /&gt;b:";print_r($b);
             echo "&lt;br /&gt;c:";print_r($c);
             echo "&lt;br /&gt;d:";print_r($d);die();
</code></pre>

<p><strong>Result</strong></p>

<pre><code>a:
b:Array ( [0] =&gt; 8 [1] =&gt; 52 ) 
c:Array ( [0] =&gt; 8 [1] =&gt; 52 ) 
d:

a:
b:
c:
d:
</code></pre>

<p><strong>Expected result</strong></p>

<pre><code>a:Array()
b:Array ( [0] =&gt; 8 [1] =&gt; 52 ) 
c:Array()
d:Array()
</code></pre>
