PHP二维数组查找是否存在某个值并且返回下标

$userdb = array(
    0 => array(
            'uid' => 100,
            'name' => 'Sandra Shush',
            'url' => 'urlof100'
        ),
 
    1 => array(
            'uid' => 5465,
            'name' => 'Stefanie Mcmohn',
            'pic_square' => 'urlof100'
        ),
 
    2 => Array(
            'uid' => 40489,
            'name' => 'Michael',
            'pic_square' => 'urlof40489'
        )
);

//var_dump(array_search(40489, array_column($userdb, 'uid')));
//考虑到性能问题，如果数组过大，array_search每次都要执行array_column()，两个函数需要分开写

$uID= array_column($userdb,'uid');

var_dump(array_search(40489, $uID));//存在返回下标，不存在返回false