I noticed that Message-ID:
<1128315722.466228.50050@o13g2000cwo.googlegroups. com> from
kai.hendry@gmail.com contained the following:

>I just wondered is there some useful maths / spec behind how to come up
>with a unique (short) ID for a resource? I would like to avoid a DBMS,
>so a hash or something?
>
>Yes I saw http://freshmeat.net/projects/shortlink/ but that's in Perl,
>I want PHP.

Which also uses a database. You want something that will compress the
text of the URL in such a way that you can reverse the algorithm and get
the original string back. Interesting challenge.

--
Geoff Berrow 0110001001101100010000000110
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