Which of the following statements is true?

What is the preferred method for preventing SQL injection?

What is the output of the following code?

var_dump(boolval([]));

After performing the following operations:

$a = array('a', 'b', 'c');

$a = array_keys(array_flip($a));

What will be the value of $a?

What is the name of the PHP function used to automatically load non-yet defined classes?

Please provide the value of the $code variable in the following statement to set an HTTP status code that signifies that the requested resource was not found.

http_response_code($code);

Given the following code, how can we use both traits A and B in the same class? (select all that apply)

trait A {

public function hello() {

return "hello";

}

public function world() {

return "world";

}

}

trait B {

public function hello() {

return "Hello";

}

public function person($name) {

return ":$name";

}

}

What is the output of the following code?

function increment ($val)

{

$_GET['m'] = (int) $_GET['m'] + 1;

}

$_GET['m'] = 1;

echo $_GET['m'];

What is the output of the following code?

function z($x) {

return function ($y) use ($x) {

return str_repeat($y, $x);

};

}

$a = z(2);

$b = z(3);

echo $a(3) . $b(2);

Consider the following table data and PHP code, and assume that the database supports transactions. What is the outcome?

Table data (table name "users" with primary key "id"):

id name email

------- ----------- -------------------

1 anna alpha@example.com

2 betty beta@example.org

3 clara gamma@example.net

5 sue sigma@example.info

PHP code (assume the PDO connection is correctly established):

$dsn = 'mysql:host=localhost;dbname=exam';

$user = 'username';

$pass = '********';

$pdo = new PDO($dsn, $user, $pass);

try {

$pdo- > exec("INSERT INTO users (id, name, email) VALUES (6, 'bill', 'delta@example.com')");

$pdo- > begin();

$pdo- > exec("INSERT INTO users (id, name, email) VALUES (7, 'john', 'epsilon@example.com')");

throw new Exception();

} catch (Exception $e) {

$pdo- > rollBack();

}