Re: Re: Create unique non-autoincrement key for700,000records?

On Tue, 2008-12-16 at 09:56 +0100, Ondrej Kulaty wrote: > Sorry you are right. He said he wants each row to have an unique ID so > AutoIncId+timestamp will satisfy it, But still i think that adding > microseconds timestamp is better because it will be harder for potential > hacker to guess. I agree, but then each entry would need ot be updated individually. Unfortunately MySQL doesn't appear to offer a time function to obtain microseconds. However, using the same argument for non collision and knowing that auto increment ID + unix_timestamp() must result in an integer, one could use the following to produce a less guessable outcome: update mytable set hash_field = md5( concat( AutoIdField + unix_timestamp(), rand() ) ) Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP