mysqli_affected_rows(): Number of Records affected

Using UPDATE Query

// Database connection file to declare $connection variable//
require "config.php"; 

$query="UPDATE  student SET class='Four'";
if ($connection->query($query)) {
echo "Records Updated : ";
echo $connection->affected_rows;
}else{
echo $connection->error;
}

Records Updated : 5

By using DELETE Query

// Database connection file to declare $connection variable//
require "config.php"; 

$query="DELETE FROM student WHERE class='Four'";
$connection->query($query);
echo " Records Deleted =  ".$connection->affected_rows;

Records Deleted = 9

By Using INSERT Query

$query="INSERT INTO student (id,name,class,mark,sex) values(100,'John','Five','80','Male')";
if($connection->query($query)){
echo "
No of records inserted : ".$connection->affected_rows;
}

No of records inserted : 1

By using SELECT Query

$query="SELECT * FROM student WHERE class='Four'";
$connection->query($query);
echo " Records returned =  ".$connection->affected_rows;

Records returned = 9

By using SELECT with LIMIT Query

$query="SELECT * FROM student WHERE class='Four' LIMIT 2,4";
$connection->query($query);
echo " Records returned =  ".$connection->affected_rows;

Records returned = 4

<?Php
require "config.php";// Database connection file.

$class='Three';
$mark=66;
$id=5;
$query="UPDATE  student SET class=?,mark=? WHERE id=?";
$stmt = $connection->prepare($query);
if ($stmt) {
$stmt->bind_param('sii', $class, $mark, $id);
$stmt->execute();
echo "Record Updated:";
echo $stmt->affected_rows;
}else{
echo $connection->error;
}
?>

$class='Three';
$mark=68;
$id=5;
$query="UPDATE  student SET class=?,mark=? WHERE id=?";
if ($stmt = mysqli_prepare($connection,$query)){
mysqli_stmt_bind_param($stmt, "sii", $class, $mark, $id);
mysqli_stmt_execute($stmt);
echo "Record Updated:";
echo mysqli_affected_rows($connection);

}else{
echo mysqli_error($connection);
}

Where to use mysqli_affected_rows