Resource id #7 when using fopen and fwrite in PHP

I'm trying to create a download link in PHP so you can download the information in a table. I just started writing it and have run into a snag. Here is what I have so far:

 <?php
 $sql = "SELECT * FROM " . $survey . ";";
 $result = mysql_query($sql)
    or die(mysql_error());
 $row = mysql_fetch_assoc($result);


 $something = "This is text";
 $myFile = "data.txt";
 $fh = fopen($myFile, 'w') or die("can't open file");

 $download_data = "";
 foreach ($row as $k=>$v){
        $download_data .= $k . "=" . $v . "\n";
 }
 fwrite($fh, $download_data);
 fclose($fh);

 echo $download_data;

 ?>
 <a href="data.txt">Download </a>

It is just supposed to show something like Code = 1 Name = John etc. When I open the txt file, it simply says Resource id #7. The weird part is, when I echo $download_data, it looks correctly in the web page. Is there something special I have to do with fwrite in order to get the whole string into the text file

(Note: I have used both mysql_fetch_array and mysql_fetch_assoc and both have the same result. Also, if I simply declare a variable like $test = "this is a test"; it works).

Edit: I have tried commenting out all other code in the script and I get the same result. Printing $download_data shows the right result, but the text file is still only showing Resource id #7. I've even tried deleting the txt file and when it is recreated, it does the same thing.

Solution

You're almost certainly not showing us the whole picture with your example code.

You are likely writing one of these things to the file:

The file handle, $fh
The result returned from mysql_query()

Check you're not mixing up $result and $row. Or even better, post all of your code.