php mysql connection get error message - php

Question

this is my first php code , i am trying to connect to a database with user name = "root" and password = "root"
i have a connection file called dbConnection.php
as following :
<?php
echo "in connection file";
$hostname = "localhost";
$username = "root";
$password = "root";
$db = "ledDB";
echo "<br> db-connection : vars definde ";
//connection to the database
$conn = mysql_connect($hostname, $username, $password)
or die("Unable to connect to MySQL");
echo "Connected to MySQL<br>";
echo "db-connection : initilize connection ";
mysql_select_db($db);
echo "db-connection : connection done";
// Check connection
echo "Connected successfully";
?>
and i call it in a file called what.php :
<?php
echo "Hello";
include "dbConnection.php";
echo "ohhhh";
?>
this returns status code 500 which is internal server error
but i want to know what is the error to fix it how can i get the error message ?
i tried
$conn = mysql_connect($hostname, $username, $password)
or die("Unable to connect to MySQL");
but it is not returning any thing.
can any one help me please ?

Answer 1

if you are having password on localhost then use password otherwise leave it blank
$con = mysqli_connect("localhost","root","yourpassword","yourdb");

Answer 2

You mysqli_connect() method.
<?php
echo "in connection file";
$hostname = "localhost";
$username = "root";
$password = "root";
$db = "ledDB";
echo "<br> db-connection : vars definde ";
//connection to the database
$conn = mysqli_connect($hostname, $username, $password)
or die("Unable to connect to MySQL");
echo "Connected to MySQL<br>";
echo "db-connection : initilize connection ";
mysqli_select_db($conn,$db);
echo "db-connection : connection done";
// Check connection
echo "Connected successfully";
?>

Answer 3

First Thing is to Change your connection method to mysqli or my personal favorite PDO.
PDO Example:
class db extends pdo{
//Website Variables
public $sitedb = '';
public $siteconfig;
public $sitesettings = array(
'host' => 'localhost',
'database' => 'yourdb',
'username' => 'youruser',
'password' => 'yourpass',
);
public function __construct(){
$this->sitedb = new PDO(
"mysql:host={$this->sitesettings['host']};" .
"dbname={$this->sitesettings['database']};" .
"charset=utf8",
"{$this->sitesettings['username']}",
"{$this->sitesettings['password']}"
);
$this->sitedb->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
}
}
$db = new db();
Then you can extend your PDO class to new classes after including the db.php page.
Example Select:
class yourclass extends db {
public function SelectUsers() {
global $db;
$query = <<<SQL
SELECT email
FROM users
WHERE active = :active
SQL;
$resource = $db->sitedb->prepare( $query );
$resource->execute( array (
':active' => 1,
));
$count = $resource->rowCount();
foreach($resource as $user){
$this->email = $user['email'];
}
}
}

Answer 4

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "mydb";
// Create connection
$conn = mysqli_connect($servername, $username, $password);
// Check connection
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
echo "Connected successfully";
// make the current db
$db_selected = mysqli_select_db ( $conn , $dbname );
if (!$db_selected) {
die ('Can\'t connect to Database : ' . mysql_error());
}
?>