| 摘要 |
In a system with cache that includes contents for each of a set of semantic regions, a query signature corresponding to a query is obtained. The query signature is used, together with a region signature for at least one of the regions, to find one or more semantic regions that are qualified and to use the contents of at least one of the qualified regions to obtain an answer to the query. The signatures can, for example, be binary strings, all having the same length. If the query and region formula are each a conjunction of terms, a signature can be obtained for each term and term signatures can be combined to obtain a query or region signature. Each signature can, for example, be a binary string, with all signatures having the same length so that signatures can be combined by performing logical operations. The query signature can be compared with the region signatures to determine whether the query is equivalent to or contained in any of the regions, in which case an answer can be obtained from cached contents. If not, another comparison can be made, either to determine whether any of the regions are contained within the query or to determine whether the query is likely to have a one-term difference with any of the regions. In these cases, a partial answer to the query can be obtained from cached contents that match the query, and a query remainder can be sent to obtain content necessary for a complete answer.
|
