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 >