PHP error in HTML - php

Question

Okay, I'm new to PHP, SQL, and HTML and I after several days I finally got my website fully coded. Now I am writing code for users to register and login. I got the register to work, but not the login.
I get the following error:
Parse error: syntax error, unexpected T_STRING in /home/u190182631/public_html/index.html on line 58
What am I doing wrong?
PHP:
<?php
$mysql_host = "xxx";
$mysql_database = "xxx";
$mysql_user = "xxx";
$mysql_password = "xxx";
$errorU = $errorP = "";
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if(empty($_POST["username"]))
{
$errorU = "Please Enter your Username";
}
if(empty($_POST["pword"]))
{
$errorP = "Please eneter a Password";
}
if ($errorU == "" && $errorP == "")
{
$con=mysqli_connect($mysql_host,$mysql_user,$mysql_password,$mysql_database);
$username = $_POST["username"];
$password = $_POST["pword"];
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($con,"SELECT * FROM Persons WHERE Username = '$username' and Password = '$password',$con) or exit('$sql failed: '.mysql_error());
$num_rows = mysql_num_rows($result);
if ($num_rows==0)
{
echo('okay');
}
else
{
echo('no');
exit;
}
}
}
?>
Form in HTML:
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>" method="post">
Username: <input type="text" name="username"><br><br>
Password: <input type="password" name="pword">
<input type="submit" value="Login">
</form>

Answer 1

You are not closing this string
$result = mysqli_query($con,"SELECT * FROM Persons WHERE Username = '$username' and Password = '$password',$con) or exit('$sql failed: '.mysql_error());
it should be
$result = mysqli_query($con,"SELECT * FROM Persons WHERE Username = '$username' and Password = '$password'") or exit('$sql failed: '.mysql_error());
On another note. Please do not use unfiltered data when getting things from a database. You will have problems with sql injection. Also don't store the password in plain text. Hash it with salt.
EDIT: You really should use PDO's. See this link: http://net.tutsplus.com/tutorials/php/why-you-should-be-using-phps-pdo-for-database-access/

Answer 2

probably you missed " in
$result = mysqli_query($con,"SELECT * FROM Persons WHERE Username = '$username' and Password = '$password',$con) or exit('$sql failed: '.mysql_error());
try:
$result = mysqli_query($con,"SELECT * FROM Persons WHERE Username = '$username' and Password = '$password',$con)" or exit('$sql failed: '.mysql_error());