Determining if an array of NULL values is considered empty
<p>I'm building an array to determine if I need to take an action. I am executing a query. The table has a <code>sent_date</code> field to determine if an email has been sent to a user or not. Once it has been sent to a user, that <code>sent_date</code> field is populated with <code>getdate()</code>. Here is how I'm building:</p>

<pre><code>$sent_date_sql = "
    select ind_id, sent_date from profileemail
";

$results = dbExec($sent_date_sql);
</code></pre>

<p>I then build my array:</p>

<pre><code>foreach ($results as $r){
    array_push($sent_date,$r['sent_date']);
    $query_count = count($results);
}
</code></pre>

<p>This all is working gloriously. My issue is when I go to check the <code>sent_date</code> array. The first time in the month that this script runs, ALL <code>sent_date</code> values are NULL. So my array looks like:</p>

<pre><code>array(228) {
  [0]=&gt;
  NULL
  [1]=&gt;
  NULL
  [2]=&gt;
  NULL
  [3]=&gt;
  NULL
  [4]=&gt;
  NULL
</code></pre>

<p>...etc.</p>

<p>Now I am going to try to evaluate <code>$sent_date</code>:</p>

<pre><code>if(empty($sent_date)){
</code></pre>

<p>My <code>empty</code> condition never hits because the values of the array are all NULL. Is there an alternative way to achieve what I am trying to do? Should I be looping through my <code>$sent_date</code> array and evaluating each value?</p>
