Re: Banner rotation with links

Kevin Murphy wrote: > On my home page i have all my banners in a MySQL database which includes > the image path, the link, and the description as separate fields. The > then do a MySQL query with a query that will look something like this: > > $query = "select * FROM banner ORDER BY RAND() LIMIT 1"; > > Seems to work just fine. just wait till you have 100000 items in that table :-) in practice that may never happen and maybe MySQL can optimize a SELECT that does "ORDER BY RAND() LIMIT 1" (can anyone confirm what MySQL does with "ORDER BY RAND() LIMIT 1" exactly in terms of scanning the table? - the MySQL docs don't mention whether this is scalable at all) *but* if that is not the case then using a field (call it 'randomized' or something like that) and indexing on that and then updating that field periodically with random integers using a cronjob script would make the resulting query alot more robust .. the compromise being that you don't get a different banner each request: $query = "select * FROM banner ORDER BY randomized LIMIT 1"; the compromise can be mitigated some what by doing something like this (assuming you use sessions): // BRC = Banner Random Count if (!isset($_SESSION['BRC'])) $_SESSION['BRC'] = 0; $query = "select * FROM banner ORDER BY randomized LIMIT {$_SESSION['BRC']},1"; $_SESSION['BRC']++; > > --Kevin Murphy > Webmaster: Information and Marketing Services > Western Nevada Community College > www.wncc.edu > 775-445-3326 > > > On Feb 14, 2007, at 8:29 AM, Chris Carter wrote: > >> >> How can I rotate a banner as well as the link in it within a page >> using PHP. >> This can be done as a include file php. Anybody please supply some >> code or a >> link for this. >> >> Thanks in advance. >> >> Chris >> --View this message in context: >> >> http://www.nabble.com/Banner-rotation-with-links-tf3228157.html#a8968148 >> Sent from the PHP - General mailing list archive at Nabble.com. >> >> --PHP General Mailing List (http://www.php.net/) >> To unsubscribe, visit: http://www.php.net/unsub.php >> > >