on http://developer.yahoo.com/answers/ here's what it say Does this mean if my site server get more then 5000 requrest a day the IP will be banned for the rest of the day ?
hmm That is a strange thing to include. Although I doubt many IP's will get you more than 5000 requests in a day.
Yes, they will not answer any more request until the next day. You can always make the request using a server side language and cache the result for a period of time (ex. 1 month or 1 day). That way, you don't need to make the request to Yahoo, every time you need the information. So if you cache all requests for 30 days, theoretically you can have access to 150,000 different api calls a day (after 30 days of caching).
My personal experience is that this limit is not counted on daily basis but on hourly basis. For example, 5000 queries a day means around 208 queries per hour. So, if your server requests Yahoo API more than 208 times an hour, your IP will be blocked for further requests for rest of that hour. I'm not sure if it is done on 1 hour basis or 2 hour basis but I have personally experienced it when my IP was blocked and unblocked several times day. Also, Yahoo is quite lenient in this regard too. They can allow you upto 10,000 or even 12,000 queries a day but it's only their unofficial leniency and not a rule.
Yahoo is not so draconian as other companies. When they ban you its only for a set period of time and not permanently.
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