im using PHP MySQL

i have this code

PHP Code:

<?    $query1 = mysql_query("SELECT, trouble_reported.code as trcode
                                FROM so_trouble_reported
                                JOIN trouble_reported ON so_trouble_reported.tr_id = trouble_reported.tr_id
                                WHERE so_trouble_reported.so_no = $so_no"); 
        $query2 = mysql_query("SELECT so_findings.findings, findings.code as fcode
                                FROM so_findings
                                JOIN findings ON so_findings.findings_id = findings.findings_id
                                WHERE so_findings.so_no = $so_no"); 
        $query3 = mysql_query("SELECT so_service_performed.sp, service_performed.code as spcode
                                FROM so_service_performed
                                JOIN service_performed ON so_service_performed.sp_id = service_performed.svc_per_id
                                WHERE so_service_performed.so_no = $so_no");                     
            <td align="center" class="txtformat1"><? echo mysql_result($query1,$ctr,'trcode')?>; <? echo mysql_result($query1,$ctr,'tr')?></td>
            <td align="center" class="txtformat1"><? echo mysql_result($query2,$ctr,'fcode')?>; <? echo mysql_result($query2,$ctr,'findings')?> </td>
            <td align="center" class="txtformat1"><? echo mysql_result($query3,$ctr,'spcode')?>; <? echo mysql_result($query3,$ctr,'sp')?></td>
          </tr><? } ?>

as u can see i have 3 queries and print its value using a mysql_result function.

i made a $ctr to print it until 4 values. if theres is a value fetched from the $query the printing is OK. but if the $query dont get values. the printing says:

Warning: mysql_result() [function.mysql-result]: Unable to jump to row 1 on MySQL result index 5 in C:\xampp\htdocs\SOMS\view_service_order.php on line 261

now what i want to do is when the $query dont retrieved any values it will print a "SPACE"

i want to put a condition were if no values retrieved it will change variables to "SPACE"
else if values retrieved print values.