PHP - How to compare two arrays and remove duplicate values

array_unique( array_merge($arr_1, $arr_2) );

or you can do:

$arr_1 = array_diff($arr_1, $arr_2);
$arr_2 = array_diff($arr_2, $arr_1);

i guess...

You can use the function array_diff in PHP that will return and array containing the keys that are the same between the two arrays.

$clean1 = array_diff($array1, $array2);

http://php.net/manual/en/function.array-diff.php