I recently found a link from a stock market website which allows me to download my raw stock data from it:
http://www.example.com/StocksHandler.ashx?{%22Type%22:%22ALL2%22,%20%22Lan%22:%22En%22}
But I'm interesting to know if I could change the parameters (in the link) to filter downloadable data? For example I may just need "BestBuyPrice" of every stock not more information; can I change link to reduce downloaded data? How can I find out what parameters are available and defined by the web designer? Is there any scanner for this?