If you just issue the next available alphanumeric sequence, as you say, the URL is always as small as possible. But the problem with that, or any other predictable sequence, is that it's open to abuse. Conversely, if you use a random number generator with a short period, as you say you'll get lots more collisions, while a long period means the URLs will be longer than necessary.

Polonius

In reply to Re^3: Long url to tiny url. by Polonius
in thread Long url to tiny url. by valavanp

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