I don’t get what the problem is.
besides that, there is no need for
$this->pdo. from the looks of it, the used PDO (statement) instance is not used outside this method. additionally, in the code right now all the $header part can be omitted (an empty array is always empty).
The computer is always right. The computer is always right. The computer is always right. Take it from someone who has programmed for over ten years: not once has the computational mechanism of the machine malfunctioned.
André Behrens, NY Times Software Developer