Steven D'Aprano <[EMAIL PROTECTED]> writes: > On Wed, 07 Sep 2005 14:31:03 -0700, jlocc wrote: >> Basically I will like to combine a social security number (9 digits) >> and a birth date (8 digits, could be padded to be 9) and obtain a new >> 'student number'. It would be better if the original numbers can't be >> traced back, they will be kept in a database anyways. Hope this is a >> bit more specific, thanks!!! > last_number_used = 123 # or some other appropriate value > > def make_studentID(): > global last_number_used > last_number_used = last_number_used + 1 > return last_number_used > > For a real application, I'd check the database to see if the number has > already been used before returning the number. Also, if you need more > than four digits in your IDs, I'd add a checksum to the end so you can > detect many typos and avoid much embarrassment. [...] > In a real application you would need to store the global variables in a > database, otherwise each time you reload the Python script you start > generating the same IDs over and over again.
For real applications (ignoring your theoretical need to generate the numbers in a random order) I'd not only store the number in the database - I'd let the databae generate it. Most have some form of counter that does exactly what you want without needing to keep track of it and check the database for consistency. <mike -- Mike Meyer <[EMAIL PROTECTED]> http://www.mired.org/home/mwm/ Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. -- http://mail.python.org/mailman/listinfo/python-list
