What are common errors when using mysqli in PHP for database connection?

One common error when using mysqli in PHP for database connection is not properly handling connection errors. It is important to check for connection errors and handle them gracefully to prevent unexpected behavior in your application. Another common error is not setting the correct character set for the connection, which can lead to encoding issues with data retrieval and storage. To solve these issues, you can use the mysqli_connect_errno() function to check for connection errors and mysqli_set_charset() function to set the character set for the connection.

// Establishing a database connection with error handling
$mysqli = new mysqli("localhost", "username", "password", "database");

if ($mysqli->connect_errno) {
    die("Failed to connect to MySQL: " . $mysqli->connect_error);
}

// Setting the character set for the connection
$mysqli->set_charset("utf8");