When should developers consider transitioning from the mysql extension to mysqli or PDO in PHP applications?

Developers should consider transitioning from the mysql extension to mysqli or PDO in PHP applications when working with MySQL databases due to the deprecation of the mysql extension in PHP 5.5 and its removal in PHP 7. To ensure compatibility and security, it is recommended to update to mysqli or PDO, which offer more features, improved security, and support for prepared statements. 

// Using mysqli to connect to a MySQL database
$mysqli = new mysqli("localhost", "username", "password", "database");

if ($mysqli->connect_error) {
    die("Connection failed: " . $mysqli->connect_error);
}

// Perform SQL queries using $mysqli object

Keywords

mysql extension mysqli PDO PHP applications transitioning

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