The attack occurs when an adversary maliciously injects text, via an unprotected input field, that is going to change a SQL statement in way that it was not intended. code example
Example: sql injection attack
$value = "your value here";
try {
$pdo = new PDO($dsn, $username, $password, $>drivers);
} catch (\PDOException $e) {
echo 'Connection Failed: ' . $e->getMessage();
}
$sql = "INSERT INTO `my_db` SET `field` = ? ";
$stmt = $this->pdo->prepare($sql);
$stmt->bindValue(1, $value, PDO::PARAM_STR);
$stmt->execute();
$stmt = null;