Creating your own TinyURL

Question

I have just found this great tutorial as it is something that I need.

However, after having a look, it seems that this might be inefficient. The way it works is, fir

Answer 1

Couldn't you just trim the hash to the length you wish?

$tinyURL = substr(md5($longURL . time()),0,4);

Granted, this may not provide as much pseudo randomness as using the entire string length. But, if you hash the long URL concatenated with the time(), wouldn't this be sufficient? Thoughts on using this method? Thanks!