Why do I keep getting a 500 error with my PHP?

Question

I am trying to create an account registration page and when I add a system to check the database and make sure that there are not multiple rows with the same username, I get a 500 error.

Here's the code that works:

<?php


if(isset ($_POST['submit']))
{
    include( 'connection.php' );

    $username = $_POST['username'];
    $password = $_POST['password'];
    $email = $_POST['email'];

    if(empty($username) || empty($email) || empty($password))
    {
        echo 'Please check the required fields.';
    }
    elseif(!filter_var($email,FILTER_VALIDATE_EMAIL))
    {
        echo 'Please enter a correct email address.';
    }
    else
    {
        $password = md5($password);
        $sql = mysql_query("INSERT INTO users (email,username,password) VALUES ('$email','$username','$password')") or die(mysql_error());

        if($sql)
        {
            echo 'Successfully submitted.';
        }
    }   
}
?>

Here's the code that gives me a 500 error:

<?php
error_reporting(E_ALL)

if(isset ($_POST['submit'])) {
    include( 'connection.php' );

    $username = $_POST['username'];
    $password = $_POST['password'];
    $email = $_POST['email'];

    $fetch = mysql_query("SELECT * FROM users WHERE username = '$email'") or die(mysql_error();
    $num_rows = mysql_num_rows($fetch);

    if(empty($username) || empty($email) || empty($password)) {
        echo 'Please check the required fields.';
    }
    elseif(!filter_var($email,FILTER_VALIDATE_EMAIL)) {
        echo 'Please enter a correct email address.';
    }

    elseif($num_rows >= 1);
    {
        echo 'This username is taken.';

    else    
    }
        $password = md5($password);
        $sql = mysql_query("INSERT INTO users (email,username,password) VALUES ('$email','$username','$password')") or die(mysql_error());

        if($sql)
        {
            echo 'Successfully submitted.';
        }
    }   
}
?>

Your code is vulnerable to SQL injections. Please look at mysql_real_escape_string, or consider PDO. — Daniel Sloof, Jul 07 '12 at 22:12
if you have installed php-cgi on your local PC then you could at least do a `php -l` to check you code for errors. It took me 60s to find the same errors as at @Jocelyn — TerryE, Jul 07 '12 at 22:18

score 3 · Answer 1 · edited Jul 07 '12 at 22:13

3

Maybe add a semi colon:

error_reporting(E_ALL);

EDIT:

You are also missing a ) on die(mysql_error();

Remove the ; from elseif($num_rows >= 1);

And then fix your else block to be } else {

edited Jul 07 '12 at 22:13

drew010

68,777
11
134
162

answered Jul 07 '12 at 22:09

Jocelyn

11,209
10
43
60

Jordan · Accepted Answer · 2014-10-13T10:54:14.227

0

You missed a semi-colon off your first statement

edited Oct 13 '14 at 10:54

answered Jul 07 '12 at 22:10

Jordan

359
3
12

score 0 · Answer 3 · answered Jul 07 '12 at 22:12

0

you have

else }

in your code. That's a syntax error. You're looking for

}
else {

instead.

answered Jul 07 '12 at 22:12

moopet

6,014
1
29
36

Why do I keep getting a 500 error with my PHP?

3 Answers3

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