Our index is partially updated every 15 minutes. We say 'partially' because the crawler can't explore the whole Internet in one second; but every couple of minutes it explores some part of it and the results become immediately available for checking in the database.
The complete database update - refreshing the info on the whole Internet backlinks - takes about two months. Within this time, some pages will be updated 60 times, others only once, depending on their rating.
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