没有找到行时，mysql_num_rows不返回任何内容

I am trying to get my head around this issue.

  $can = $r6['candidate_id'] ; 
  $checkquery = mysql_query("SELECT * FROM candidate 
  WHERE candidate_id ='$can' and type='facrep'") or die(mysql_error());  
  if (mysql_num_rows($checkquery) > 0) {
     echo ">0" ; 
  }else {
     echo "0" ; 
  }

If there is a record in the database, it succesfully returns >0 but if there are no records, it doesn't return anything, not even 0. Consequently, the else statement never works.

Ideas?

The mysql_num_rows returns bool false on no rows found.So you to re-write the code as

  $can = $r6['candidate_id'] ; 
  $checkquery = mysql_query("SELECT * FROM candidate 
  WHERE candidate_id ='$can' and type='facrep'") or die(mysql_error());  
  if (mysql_num_rows($checkquery)) {
     echo ">0" ; 
  }else {
     echo "0" ; 
 }

this would help you out hopefully!