Question

I have a php comma seperated string
$string = (x,y,z)

I have a column in mysql that has items (y,z)

how do i compare the two and echo which items in $string are not in the column?

Answer 1

I think you want to compute differente in two comma separated strings.

Just convert your strings in to array using explode and use array_diff

array_diff – Computes the difference of arrays

Example :

<?php

$array1=explode(",",$string);
$array2=explode(",",$yourstring_of_db_column);
$array1 = array("x", "y", "z");
$array2 = array( "y","z");
$result = array_diff($array1, $array2);

print_r($result);
?>

Be aware Values are compared using ===, so 1 and “1” are considered different.