How to work with mysqli

How to connect to a MySQL database (object-oriented)

$host = 'localhost'; 
$username = 'mgs_user'; 
$password = 'pa55word'; 
$db_name = 'my_guitar_shop1'; 
$db = new mysqli($host, $username, $password, $db_name);

How to connect to a MySQL database (procedural)

$host = 'localhost'; 
$username = 'mgs_user'; 
$password = 'pa55word'; 
$db_name = 'my_guitar_shop1'; 
$db = mysqli_connect($host, $username, $password, $db_name);

Two properties of the mysqli object for checking connection errors

Property	Description
connect_errno	Returns the error number if an error occurred. Returns a NULL value if no error occurred.
connect_error	Returns the error message if an error occurred. Returns a NULL value if no error occurred.

How to check for a connection error (object-oriented)

$connection_error = $db->connect_error; 
if ($connection_error != null) { 
  echo("Error connecting to database: $connection_error");
  exit(); 
}

How to check for a connection error (procedural)

$connection_error = mysqli_connect_error(); 
if ($connection_error != null) { 
  echo("Error connecting to database: $connection_error");
  exit(); 
}

Description

The mysqli extension includes a procedural style that uses functions to work with the database, and it includes an object-oriented style that uses objects, methods, and properties to work with the database.
To suppress errors, you can begin the line of code that connects to the database with the error suppression operator (@).

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