How can mixing object-oriented and procedural MySQLi functions lead to errors in PHP?

Mixing object-oriented and procedural MySQLi functions can lead to errors in PHP because they use different connection methods. To avoid conflicts, it is best to stick to one style consistently throughout your code. If you are using object-oriented MySQLi functions, do not mix them with procedural functions and vice versa. 

// Object-oriented approach
$mysqli = new mysqli("localhost", "username", "password", "database");

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

// Perform queries using object-oriented style
$result = $mysqli->query("SELECT * FROM table");

// Procedural approach
$link = mysqli_connect("localhost", "username", "password", "database");

if (!$link) {
    die("Connection failed: " . mysqli_connect_error());
}

// Perform queries using procedural style
$result = mysqli_query($link, "SELECT * FROM table");

// Close the connections
$mysqli->close();
mysqli_close($link);

Keywords

MySQLi object-oriented procedural errors PHP

Related Questions