Sorry, may be it's a dumb question but I'm a newbie and trying to understand how the stuff works. There are many affiliate sites that allow you to search for a particular product in many stores and return you availability + price info + an affiliate link that leads to the product page. Technically, when the user submits the search form, where do price comparison sites take the price info from? Few possibilities:
(1) The search form activates CGI script that reads the price info in "real-time" from the merchant site and then generates HTML with the price to the user. (pros: always updated info, cons: takes time to gather all data, slow response)
(2) All the price data is stored locally on the affiliate site in some kind of database. (pros: fast response, cons: info may be outdated)
How is it actually done? If the option (2) is used how the data coherency with the merchant site is kept? Merchant can update the price, or the product may be out of stock....
I'll appreciate your replies.