8. The method of claim 4 , further comprising: identifying records having corresponding intervals that overlap the defined interval from the search query; and for each of the logical combination of terms in the set defined by the search query, generating the estimate for the number of occurrences of the logical combination of terms in the records having corresponding intervals that overlap the defined interval from the search query.
8. The method of claim 4 , further comprising: identifying records having corresponding intervals that overlap the defined interval from the search query; and for each of the logical combination of terms in the set defined by the search query, generating the estimate for the number of occurrences of the logical combination of terms in the records having corresponding intervals that overlap the defined interval from the search query. 9. The method of claim 8 , wherein: at least two of the log streams are partitioned into sequences of records having different size intervals; and identifying records having corresponding intervals that overlap the defined interval from the search query identifies a plurality of records of different ones of the log streams that overlap the defined interval from the search query.