Cold Fusion & MySQL sort and display unique database items

I have a database that contains customer photos, text associated with those including Names, website, customer number and membership level. I need to show groups of photos on web pages (typically a group of 3) but they have to be unique for each page load. Also customers at different membership levels get their picture shown at different frequencies. So for example, lets say I have gold level clients and bronze level. Gold level get their picture shown twice as often as bronze. So when a page loads, I need 3 unique pictures shown (no repeats), and gold needs to be shown twice as often as bronze. I would like the program to be easily configurable so that I could show groups of say 2 photos on one page and a group of 3 on another. Also, it is desirable to be able to call this code more than once on a page and still have no repeats. For example, show one picture at the top of the page and 3 in the middle.