31. The system of claim 21 , wherein the conditionally scheduling the corresponding document for indexing based on the result assigns the document to a periodic crawl layer when the result is deemed satisfactory.
31. The system of claim 21 , wherein the conditionally scheduling the corresponding document for indexing based on the result assigns the document to a periodic crawl layer when the result is deemed satisfactory. 32. The system of claim 31 , wherein the periodic crawl layer is a daily crawl layer.