Possible to call PDO::fetchAll() more then once?

Ive been running some queries using PHP's PDO library. It seems that whe开发者_如何学运维n i use:

<?php
    $smtp->execute();
    $result = stmt->fecthArray();
?>

It unsets the array inside PDO. I know this because when i call that very same line again, it returns an empty array. Why does it do this? Is this normal behavior?

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When building the resulting array, fetchAll() removes all the results from the result set. Instead of calling it again, re-use the array you retrieved in the first time.