title: PDO fetchAll array to one dimensional
body: <p>this may be a simple question but am struggling to understand how to solve it. I have a form which allows the user to select either "custom" or "all" staff" to assign to a job.</p>
  
  <p>If custom is selected the user selects staff by clicking each checkbox, I then insert these into a jobs table. This produces the array below (3, 1, 10 are the staff IDs)</p>
  
  <pre><code>Array
  (
      [0] =&gt; 3
      [1] =&gt; 1
      [2] =&gt; 10
  )
  </code></pre>
  
  <p>If "all staff" is selected, I first query a select statement to get all the staff ID's from the staff table, and then insert these into the job table the same as above. However this produces the array :</p>
  
  <pre><code>Array
  (
      [0] =&gt; Array
          (
              [staffID] =&gt; 1
              [0] =&gt; 1
          )
  
      [1] =&gt; Array
          (
              [staffID] =&gt; 23
              [0] =&gt; 23
          )
  
      [2] =&gt; Array
          (
              [staffID] =&gt; 26
              [0] =&gt; 26
          )
  
      [3] =&gt; Array
          (
              [staffID] =&gt; 29
              [0] =&gt; 29
          )
  )
  </code></pre>
  
  <p>How can I convert the array above to the first array shown? </p>
  
  <p>I'm using the code below to query the database to get all the staff ID's and then inserting them.</p>
  
  <pre><code>    $select = $db-&gt;prepare("SELECT staffID FROM staff");
      if($select-&gt;execute())
      {
         $staff = $select-&gt;fetchAll();
      }
  
      for($i = 0; $i&lt;count($staff); $i++)
      {
      $staffStmt = $db-&gt;prepare("INSERT INTO staffJobs (jobID, userID) VALUES (:jobID, :staffID)");
      $staffStmt-&gt;bindParam(':jobID', $jobID, PDO::PARAM_INT);
      $staffStmt-&gt;bindParam(':staffID', $staff[$i], PDO::PARAM_INT);
  
      $staffStmt-&gt;execute();              
  
  }
  </code></pre>
  
  <p>The first array inserts fine, however the last array inserts zeros for the staffID.</p>
  
  <p>Any suggestions?</p>
  
  <p>Thanks =).</p>