PHP deletes the element of the associative array with its position

I have an associative array like this:

$arr = array('id' => 3, 'title' => 'lorem ipsum');

Now, I want to remove first element from array regardless of it's key, because 'id' can sometimes be 'm_id', 'e_id'...

That is why I can't use unset['id'], but I can't use unset[0] either, because 0 is not it's key.

How do I do that?

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array_shift($arr);

For the array $arr = array('id' => 3, 'title' => 'lorem ipsum');, this will return 3and change the array $arr to $arr = array('title' => 'lorem ipsum');.

Docs: http://php.net/manual/en/function.array-shift.php