How do i create the array with the values being fetched from database in php

[fleliaway]

Say i am having set of rows in a table and each row is having a column called city with some values assigned to it iam iterating through the result set and i need to assign the list of city values of each row in to an array only unique\[code\] foreach($res as $row){ $cities =array(); $cities[] = $row['city']; //when i say var_dump($cities); //Iam not able to get array .how do i do that $maincities = array('A','B',C) }\[/code\]