connecting to database

Hi everyone
could any one tell me what is wrong with this code,when I run it, dose not insert data into the database. i did create the database and the table . Thanks a lot

<?php
$con = mysql_connect("localhost","","");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }
	mysql_select_db("my_db", $con)
	or die("can not connected to selected " . mysql_error());
	$sql="INSERT INTO person (FirstName, LastName, Age)
VALUES
('$_POST[firstname]','$_POST[lastname]','$_POST[age]')";
if (!mysql_query($sql,$con))
  {
  die('Error: ' . mysql_error());
  }
echo "1 record added";
mysql_close($con)
?>

PHP:

 

$con = mysql_connect("localhost","","");

Are you using:

$con = mysql_connect("localhost","username","password");

And:

mysql_select_db("your_databas_name", $con)

 

Your arrays are wrong.
Fix it to this

$sql="INSERT INTO person (FirstName, LastName, Age)
VALUES
('{$_POST['firstname']}','{$_POST['lastname']}','{$_POST['age']}')";

PHP:

And this is very vulnerable to sql injections, since you are directly querying from raw post data.

 

when doing sql query, add curly brackets to the array-type variable

{$_POST['name']}

PHP:

 

How can you connect without using a username in the connection?

$con = mysql_connect("localhost","","");

PHP:

You should have at least 1 username and the user should have proper privillege in the database to insert/select/update etc.

Try using the default one, if you don't create an user.

$con = mysql_connect("localhost","root","");

PHP: