Soring an array

Hi! I am new on this list, so i welcome everybody! /sorry if my english is not too good/ My problem is: I want to sort an array. I found the array_multisort funciton in the help, but that is for multidimensional arrays, or 2 or more arrays. What i need exactly. I have 5 MySQL tables, and i want to collect some informations from all theese tables, and then get out only the different items. Like: 1st table: 1,2,3 2nd: 2,4,3 3rd: 5,1,5 I need an array, what will include 1,2,3,4,5 So i thought, i collect all the numbers in 1 array, then sort it, and then get out the duplicat items. Any suggestion ? Thx Vaso