[Zope] Unique IDs

Oliver Bleutgen Oliver Bleutgen <myzope@gmx.net>
Sun, 10 Jun 2001 16:12:52 +0200


>> Or is there a better way of doing it?

> One additional: using a hash algorithm does produce unique values in
> many cases but doesn't guarantee them. If uniqueness is an absolute
> requirement you have to check if a key already exists and generate
> another one in this case (using a different secret f.e.).


Hm,
out of interest, is there a way to be sure to get
atomicity for the above algorithm?
Otherwise there is always a small timespan in
which an object with the same name could have
been created - after the above check, but before
you create it.

Wouldn't it be simpler (in typical zope cases)
to just try to create the objects in the same 
folder and just wrap the id generation 
and object creation in a try/except clause?

And additionally  - instead of using hashes - 
just to use a timestamp?

cheers,
oliver