Martin Zvarík wrote:
I want to store the file's hash to the database, so I can check next
time to see if that file was already uploaded (even if it was renamed).
What would be the best (= fastest + small chance of collision) algorithm
in this case?
"Fastest" depends mostly on the size of the file, not the algorithm
used. A 2gig file will take a while using md5 as it will using sha1.
Using md5 will be slightly quicker than sha1 because generates a shorter
hash so the trade-off is up to you.
$ ls -lh file.gz
724M 2008-07-28 10:02 file.gz
$ time sha1sum file.gz
4ae7bd1e79088a3e3849e17c7be989d4a7c97450 file.gz
real 0m3.398s
user 0m3.056s
sys 0m0.336s
$ time md5sum file.gz
16cff7b95bcb5971daf1cabee6ca4edd file.gz
real 0m2.091s
user 0m1.744s
sys 0m0.328s
$ time sha1sum file.gz
4ae7bd1e79088a3e3849e17c7be989d4a7c97450 file.gz
real 0m3.332s
user 0m2.988s
sys 0m0.344s
$ time md5sum file.gz
16cff7b95bcb5971daf1cabee6ca4edd file.gz
real 0m2.136s
user 0m1.776s
sys 0m0.348s
--
Postgresql & php tutorials
http://www.designmagick.com/
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php
