1. A method for building an index, comprising: building a new index i+1 and outputting an anchor text table i+1 and a duplicates table i+1 using a store i , a delta store, and previously generated global analysis computations i , wherein the previously generated global analysis computations i include an anchor text table i , a rank table i , and a duplicates table i ; and generating new global analysis computations i+1 using the anchor text table i+1 , the duplicates table i+1 , and the previously generated global analysis computations i .