A question on using randomblob(16) to generate UUIDs, as the SQLite docs suggest: what assurance do you have that the UUID really is universally unique? It's a pseudo-random number, and you can replicate a stream of pseudo-random numbers by setting the seed appropriately. Is randomblob() doing some kind of magic in its seeding of the random number stream?
Will On 1/24/11 3:49 AM, "Alexey Pechnikov" <pechni...@mobigroup.ru> wrote: See http://sqlite.mobigroup.ru/dir?name=ext/uuid 2011/1/24 sqlite-us...@h-rd.org <sqlite-us...@h-rd.org> > Hi, > > I have put together a simple uuid generation method in sqlite: > > select '{' || hex( randomblob(4)) || '-' || hex( randomblob(2)) > || '-' || '4' || substr( hex( randomblob(2)), 2) || '-' > || substr('AB89', 1 + (abs(random()) % 4) , 1) || > substr(hex(randomblob(2)), 2) || '-' || hex(randomblob(6)) || > '}'; > > It's based on the description for v.4 uuid's in wikipedia > https://secure.wikimedia.org/wikipedia/en/wiki/Uuid . > > But I am thinking there may be a better (or another) method to do this > in sqlite, without the need to use something external? > > thanks > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- Will Duquette -- william.h.duque...@jpl.nasa.gov Athena Development Lead -- Jet Propulsion Laboratory "It's amazing what you can do with the right tools." _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
