SQL Array into Array based function

Question

Default Set Up

$stream->setTrack (array('cookie'));

Trial

$sql = "SELECT DISTINCT text FROM keywords"; $query = mysql_query($sql) or die($sql . ' - ' . mysql_error());
$keys = array();
 while ($row = mysql_fetch_array($query)) {
 $keys[] = $row[0];
}$stream->setTrack ($keys);

The default set up takes the written word and places it into an array The trial set up should retrieve a set of keywords from a mysql table as an array and insert them into the function.

It doesn't work. What's wrong?

public function setTrack($trackWords)
{
$trackWords = ($trackWords === NULL) ? array() : $trackWords;
sort($trackWords); // Non-optimal, but necessary
if ($this->trackWords != $trackWords) {
  $this->filterChanged = TRUE;
}
$this->trackWords = $trackWords;
}