Error after Server Upgrade - mysql_num_rows(): supplied argument is not a valid MySQL result resource

Question

I tried to search and found some similar questions but none seemed to help with my code. I upgraded to a new server:

MySQL = 5.0.96-community
PHP = 4.4.9

I get following error:

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /path/to/file/filename.php on line 209

Here's the Line 209:

$num_rows = mysql_num_rows($result);

The code right above it for reference is:

<?

// Connect to DB

$db = mysql_connect("localhost","db_name","password");

if (!$db)
{
echo "No connection.";
exit;
}

mysql_select_db("db_name");

$v = str_replace(' ','_',$v);

$query = "SELECT * FROM reviews";
$result = mysql_query($query);

$num_rows = mysql_num_rows($result);

You've upgraded to PHP/4.4.9 in 2014? What prior version were you using? — Álvaro González, Jan 08 '14 at 17:04
Did you check the mysql_error - `mysql_query($query) or die(mysql_error());` — Krish R, Jan 08 '14 at 17:05
You _upgraded_ to PHP 4.4.9? You know that was released 3.5 years ago, and support was discontinued even before that? — Clive, Jan 08 '14 at 17:05
@Clive - you mean they discontinued support even before releasing it? — Mark Baker, Jan 08 '14 at 17:07
@Clive - PHP/4.4.9 was [released in 2008](http://www.php.net/ChangeLog-4.php#4.4.9). — Álvaro González, Jan 08 '14 at 17:09
@ÁlvaroG.Vicario Yep, and support for PHP 4 "has been discontinued since 2007-12-31". See the link... — Clive, Jan 08 '14 at 17:09
@MarkBaker Sorry, you're right. 5.5 years. Support for PHP4 was discontinued in 2007 though, so still earlier — Clive, Jan 08 '14 at 17:11

score 0 · Answer 1 · answered Jan 08 '14 at 17:07

You aren't doing basic error checking:

$result = mysql_query($query);

For SELECT, SHOW, DESCRIBE, EXPLAIN and other statements returning resultset, mysql_query() returns a resource on success, or FALSE on error.

For other type of SQL statements, INSERT, UPDATE, DELETE, DROP, etc, mysql_query() returns TRUE on success or FALSE on error

Error after Server Upgrade - mysql_num_rows(): supplied argument is not a valid MySQL result resource

1 Answers1