Create a Prepared Statement
function insertValues($value_1, $value_2, $value_3) {
$conn = $this -> getConnection();
$stmt = $conn -> prepare("INSERT INTO Table_Name (Column_1, Column_2, Column_3) VALUES (?, ?, ?)");
$stmt -> bindParam(1, $value_1);
$stmt -> bindParam(2, $value_2);
$stmt -> bindParam(3, $value_3);
$success_result = $stmt -> execute(); // returns bool
return $success_result;
}