elseif statement if mysql_affected_rows = -1

[HDFilmMaker2112]

I'm having an issue redirecting my page to an error page if my UPDATE query does not find a matching entry to update:

 

elseif($_GET['forgot']=="password"){

$new_password =& generatePassword();
$username=sanitize($_POST['username']);

$sql1="UPDATE $tbl_name SET password='$new_password' WHERE username='$username' AND email='$email' AND amount='$donation_amount'";
$result1=mysql_query($sql1);
$num_rows1=mysql_affected_rows();

if($num_rows1==1){
$content.='<p class="center">New password generated. It has been emailed to the email address provided.</p><br />';
$message='Some one (hopefully you) requested a new password be generated for your account on Make the Movie Happen.
Below is the newly generated password:

Password: '.$new_password.'

Once you log-in, please change your password.

Thank You,
Make the Movie Happen Support Team
';
mail($email, 'Make the Movie Happen - New Password', $message, 'From: general@makethemoviehappen.com');
}
elseif($num_rows1=="-1"){
header("Location: ./index.php?forgot&e=1");
}
else{
$content.='New password could not be generated. 
If you continue to have issues, please email <a href="mailto:general@makethemoviehappen.com">general@makethemoviehappen.com</a> for assistance.';
}
}

mysql_affected_rows should return a positive number if it finds rows to update and -1 if the query fails. I thought if it didn't find anything to update the query would fail... should it be 0 instead of -1?

 

 

Here's where the page redirects if it doesn't find anything to update.

else{
$content='<div class="main">
<div class="main_header clear">Forgot Password/Username</div>
<br />
<div>
<p class="eighteen">Forget Password</p>
<p>Enter the information below to reset your password.</p>';
if($_GET['e']=="1"){
$content.='<p class="red">Information entered incorrect.</p>';
}
$content.='
<form action="./index.php?forgot=password" method="post">
    <p><label>Username:</label> <input type="text" name="username" size="30" /></p>
<p><label>E-Mail of Original Donation/Purchase:</label> <input type="text" name="email" size="32" /></p>
<p><label>Total Donation Amount:</label> <input type="text" name="donation_amount"  size="5" /> <span class="twelve">(In x,xxx.xx format. Any other format will cause an error.)</span></p>
    <p><input type="submit" value="Submit" name="Submit" /></p>
    </form>
</div>
<br />
<div>
<p class="eighteen">Forget Username</p>
<p>Enter the information below to have your username emailed to you.</p>';
if($_GET['e']=="2"){
$content.='<p class="red">Information entered incorrect.</p>';
}
$content.='
<form action="./index.php?forgot=username" method="post">
<p><label>E-Mail of Original Donation/Purchase:</label> <input type="text" name="email" size="32" /></p>
<p><label>Total Donation Amount:</label> <input type="text" name="donation_amount"  size="5" /> <span class="twelve">(In x,xxx.xx format. Any other format will cause an error.)</span></p>
    <p><input type="submit" value="Submit" name="Submit" /></p>
    </form>
</div>
</div>
<br />
';
}

[PFMaBiSmAd]

In the mysql_affected_rows documentation, a failed query means one that failed due to an error when the query was tried (sql syntax error, wrong table/column names, problem with the database connection...)

 

Zero affected rows means that the query executed, without any errors, but no row was affected.