connect.php failing to connect

Question

I want a website to connect to a database with a connect.php so i created a small test in it. but it is failing only showing Database Connection Failed with no mysql error. here is the code:

<?php
$servername = "localhost";
$username = "sqluser";
$password = "Welkom01!";
$dbname = "users";

$connection = mysqli_connect('$servername', '$username', '$password');
if (!$connection){
    die("Database Connection Failed". mysqli_error());
}
$select_db = mysqli_select_db($dbname);
if (!$select_db){
die("Database Selection Failed" . mysqli_error());
}
echo "succes";
?>

could you guys help me out? thanks in advance

Answer 1

Remove the single quotes around your variables:

$connection = mysqli_connect($servername, $username, $password');

PHP treats the contents of single quotes as strings. Only double quotes will evaluate variables correctly:

<?php
$username = 'foo';
echo '$username'; // outputs: '$username'
echo "$username"; // outputs: 'foo';
echo $username; // outputs : 'foo';

Also, your mysqli_select_db is incorrect. It should be:

$select_db = mysqli_select_db($connection, $dbname);

As Fred pointed out below, mysqli_error requires the connection to be passed in:

if (!$select_db){
    die("Database Selection Failed" . mysqli_error($connection));
}

Answer 2

If you use single quotes in a method/function, the interpreter will not assign the variable value.

A solution might be:

$connection = mysqli_connect($servername, $username, $password);

You also need to pass the linkid ($connection) when selecting your database.

$select_db = mysqli_select_db($connection, $dbname);

Answer 3

Try this :

<?php
$servername = "localhost";
$username = "sqluser";
$password = "Welkom01!";
$dbname = "users";

$connection = mysqli_connect($servername, $username, $password);
if (!$connection){
    die("Database Connection Failed". mysqli_error($connection));
}
$select_db = mysqli_select_db($connection,$dbname);
if (!$select_db){
die("Database Selection Failed" . mysqli_error($connection));
}
echo "succes";
?>