Php: Hit Count . Error :mysql_num_rows() expects parameter 1 to be resource

Question

Possible Duplicate:
mysql_fetch_array() expects parameter 1 to be resource, boolean given in select

Hey I am making a unique hit counter.

<?php  
$ip_add = $_SERVER['REMOTE_ADDR'];

function ip_exists($ip){
  global $ip_add;
  $query = "SELECT 'ip_count' from 'count_ip' where 'ip_count' = '$ip_add'";
  $query_run = mysql_query($query);
  $query_num_rows = mysql_num_rows($query_run);

  if($query_num_rows == 0){
    return false;
  }
  else if($query_num_rows >= 1){
    return true;
  }
}

if(ip_exists($ip_add)) {
  echo " exists";
} else {
  echo "doesnt";
}
...

I am getting this Error:

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in 
C:\wamp\www\php\Hit Counter\index.php on line 18

The error is on here:

$query_num_rows = mysql_num_rows($query_run);

Please stop writing new code with the ancient `mysql_*` functions. They are no longer maintained and community has begun the [deprecation process](http://news.php.net/php.internals/53799). Instead you should learn about prepared statements and use either [PDO](http://php.net/pdo) or [MySQLi](http://php.net/mysqli). If you care to learn, [here is a quite good PDO-related tutorial](http://wiki.hashphp.org/PDO_Tutorial_for_MySQL_Developers). — Madara's Ghost, May 15 '12 at 18:39

DaveRandom · Accepted Answer · 2012-05-15T18:53:06.847

Firstly, we see in the error message that there was a boolean given - the only reason mysql_query() returns a boolean for a SELECT query is if the query failed - which it will have done because you have a syntax error in your SQL. You need to change some of the single quotes to backticks:

$query = "
  SELECT `ip_count`
  FROM `count_ip`
  WHERE `ip_count` = '$ip_add'
";

Object names (columns, tables etc) should be quoted with backticks `, anything surround with single quotes ' is treated as a literal string.

You need to check for the failure of the query:

$query_run = mysql_query($query);
if (!$query_run) {
  // Handle error here
}
$query_num_rows = mysql_num_rows($query_run);

Some additional comments:

Try and indent your code more sensibly, it will make it much easier to debug in the long run
Avoid the use of global variables, they are very bad practice, especially when you are populating them with data that is already superglobal
Make sure you escape any data from external sources before using it in a database query
Don't use the mysql_* functions, use PDO or MySQLi

Awesome answer , Really impressed :) Thanks – Jasminder Pal Singh May 16 '12 at 12:20 — Jasminder Pal Singh, May 16 '12 at 12:20

score 1 · Answer 2 · answered May 15 '12 at 18:41

Test your query to make sure it is being executed properly:

<?php
...
$query_run = mysql_query($query);
if (!$query_run) {
  die('Invalid query: ' . mysql_error());
} else {
  // continue your code
}
?>

Like this, if the query fails, you can obtain some feed back to analyze!

See this: mysql_query Example, #1 Invalid Query

score 0 · Answer 3 · answered May 15 '12 at 18:41

mysql_query() returns a boolean, whether the query succeeded or not. If you want to pass in the correct argument, you need to assign the connection handler to a variable, and pass that in.

$conn = mysql_connect()...
...
$query_num_rows = mysql_num_rows($conn);

Though you should not use mysql_* functions anymore! See my comment on your question!

score 0 · Answer 4 · answered May 15 '12 at 18:43

Actually the query has syntax error which causes the $query_run() to return an error instead of the actual output. You have to be careful while using the quotes in queries. replace the query like this:

$query = "SELECT ip_count from count_ip where ip_count='$ip_add'";

If $ip_add is not a string, avoid single quotes there too. avoid quotes if you are writing a field name or a table name. You need a quote only where you write a string.

Php: Hit Count . Error :mysql_num_rows() expects parameter 1 to be resource

4 Answers4