RE: [PHP] Unique random string

I have not been following this thread that closely, but as I recall you wanted a unique id from requests from several machines. I don't know if anyone mentioned: $id = $machine_name . time() . uniqid() I have used that to create keys for database entries. If you want a shorter code, convert the machine name to a code and use less date info, etc. > -----Original Message----- > From: Henrik Johansson [mailto:henrik.johansson@radius.se] > Sent: Wednesday, June 28, 2000 4:52 AM > To: 'Dan' > Cc: 'php-general@lists.php.net' > Subject: RE: [PHP] Unique random string > > > That´s a good approach! > Using the time()-function in php would implement this nicely as it > returns the number of seconds since the 1st January 1970. > To avoid more than one user to register email-alias during the > one-second interval it takes time() to increment, a table-lock could be > issued and released after it´s been verified that the time() has in fact > incremented one second. > > Happy Hacking, > Henrik J. > > > ---------- > > From: Dan[SMTP:dan@savage-comedy.com] > > Sent: den 28 juni 2000 13:26 > > To: php-general@lists.php.net > > Subject: FW: [PHP] Unique random string > > > > Why not just have an integer that gets incremented. Represent > it as a 14 > > digit hex number. Use the 15th digit as a prefix for the year.. > > 1AAAAAAAAAAA > > is year one, 2AAAAAAAA is the second year, and so on. > > > > If you need to check them against previous strings, build a > table for that > > year of only the IDs you've generated with '1', the next year > '2', etc. It > > should be a small subset of all of your random IDs. > > > > Dan Sevush > > CTO Dan's Chocolates > > Happy PHP site since 11/99 > > www.danschocolates.com > > > > > > > -----Original Message----- > > > From: William Ahern [mailto:wahern@mailshell.com] > > > Sent: Tuesday, June 27, 2000 7:35 PM > > > To: php-general@lists.php.net > > > Subject: [PHP] Unique random string > > > > > > > > > Any ideas on how I can generate a 'guaranteed' unique ascii > > > string less than > > > 15 characters. > > > > > > It must be guaranteed unique across several independent > > > servers. > > > > > > Currently we are generating random short strings to create > > > unique aliases for > > > email addresses. The only problem is that to guarantee > > > uniqueness we keep a log > > > of previous strings and check to make sure we don't create > > > duplicates (we cannot > > > rotate strings. They must be absolutely unqiue for the next > > > decade or so). > > > > > > The optimal solution would be to generate strings that are > > > truly unique and > > > hopefully random enough, w/o having to go through the process > > > of checking for > > > duplicates. > > > > > > I'd use uniqid(), except that it is 32 characters (too long > > > since users will > > > have to handle them sometimes) and the algorithm must be > > > available to C, C++, > > > Perl, whatever. > > > > > > Any comments, suggestions or answers! ;) would be great. > > > > > > Please add my address to the reply as I am not subscribed > to the list. > > > > > > TIA, > > > > > > Bill > > > > > > -- > > > PHP General Mailing List (http://www.php.net/) > > > To unsubscribe, e-mail: php-general-unsubscribe@lists.php.net > > > For additional commands, e-mail: php-general-help@lists.php.net > > > To contact the list administrators, e-mail: > > > php-list-admin@lists.php.net > > > > > > > > > -- > > PHP General Mailing List (http://www.php.net/) > > To unsubscribe, e-mail: php-general-unsubscribe@lists.php.net > > For additional commands, e-mail: php-general-help@lists.php.net > > To contact the list administrators, e-mail: > php-list-admin@lists.php.net > > >