functions that take variable arguments?

how do you create/use a function that takes an undefined amount of arguments? I looked at the manual but its a little confusing. for example, i want to make a function called Update inside a DB class: class DB { //vars here var $host; var $DbUser; //functions function Update(...) { //this function can take as few as 1 argument or as many as php will allow //its supposed to update a database with the new values of the arguments. //any help getting started on creating a function like this would be apreciated } //end class } thanks