Hello,
The table below with mysql_query($sqlStr3) (the one with the word "Joined" in its row) does not echo if the result associated with mysql_query($sqlStr1) has a value of zero.  This happens even if mysql_query($sqlStr3) returns a result.
In other words, if a given loginid has an entry in the table "login", but not one in the table "submission", then the table associated with mysql_query($sqlStr3) does not echo.  
I don't understand why the "submission" table would have any effect on mysql_query($sqlStr3), since the $sqlStr3 only deals with another table, called "login", as seen below.  
Any ideas why this is happening?
Thanks in advance,
John W.
<?php
echo '<div class="profilename">User Profile for </div>';
echo '<div class="profilename2">'.$profile.'</div>';
$tzFrom = new DateTimeZone('America/New_York'); 
$tzTo = new DateTimeZone('America/Phoenix'); 
  $profile = mysql_real_escape_string($_GET['profile']);
  $sqlStr = "SELECT l.username, l.loginid, s.loginid, s.submissionid, s.title, s.url, s.datesubmitted, s.displayurl
               FROM submission AS s
         INNER JOIN login AS l
                 ON s.loginid = l.loginid
              WHERE l.username = '$profile'
           ORDER BY s.datesubmitted DESC";
  $result = mysql_query($sqlStr);
$arr = array(); 
echo "<table class=\"samplesrec1\">";
while ($row = mysql_fetch_array($result)) { 
    $dt = new DateTime($row["datesubmitted"], $tzFrom); 
    $dt->setTimezone($tzTo);
    echo '<tr>';
    echo '<td class="sitename3">'.$dt->format('F j, Y &\nb\sp &\nb\sp g:i a').'</a></td>'; 
    echo '<td class="sitename1"><a href="http://www.'.$row["url"].'">'.$row["title"].'</a></td>';
    echo '</tr>';
    }
echo "</table>";    
  $sqlStr1 = "SELECT l.username, l.loginid, s.loginid, s.submissionid, s.title, s.url, s.datesubmitted, s.displayurl, l.created, count(s.submissionid) countSubmissions
               FROM submission AS s
         INNER JOIN login AS l
                 ON s.loginid = l.loginid
              WHERE l.username = '$profile'";
  $result1 = mysql_query($sqlStr1);
$arr1 = array(); 
echo "<table class=\"samplesrec2\">";
while ($row1 = mysql_fetch_array($result1)) { 
    echo '<tr>';
    echo '<td class="sitename5">Submissions:      '.$row1["countSubmissions"].'</td>';
    echo '</tr>';
    }
echo "</table>";    
  $sqlStr2 = "SELECT l.username, l.loginid, c.loginid, c.commentid, c.submissionid, c.comment, c.datecommented, l.created, count(c.commentid) countComments
               FROM comment AS c
         INNER JOIN login AS l
                 ON c.loginid = l.loginid
              WHERE l.username = '$profile'";
  $result2 = mysql_query($sqlStr2);
$arr2 = array(); 
echo "<table class=\"samplesrec3\">";
while ($row2 = mysql_fetch_array($result2)) { 
    echo '<tr>';
    echo '<td class="sitename5">Comments:          '.$row2["countComments"].'</td>';
    echo '</tr>';
    }
echo "</table>";    
$tzFrom3 = new DateTimeZone('America/New_York'); 
$tzTo3 = new DateTimeZone('America/Phoenix'); 
  $sqlStr3 = "SELECT created, username
               FROM login 
              WHERE username = '$profile'";
  $result3 = mysql_query($sqlStr3);
$arr3 = array(); 
echo "<table class=\"samplesrec4\">";
while ($row3 = mysql_fetch_array($result3)) { 
    $dt3 = new DateTime($row3["created"], $tzFrom3); 
    $dt3->setTimezone($tzTo3);
    echo '<tr>';
    echo '<td class="sitename5">Joined:                  '.$dt->format('F j, Y').'</td>';
    echo '</tr>';
    }
echo "</table>";    
?>
</body>
</html>