| 摘要 |
The present invention relates to a method and apparatus for extracting information from a database. Information is extracted from a database using a computer-implemented method that involves a sequential chain of main calculations, in which a first main calculation operates a first selection item on a data set to produce a first result, and a second main calculation operates a second selection item on the first result to produce a second result. The first and second results are cached in computer memory for re-use in subsequent iterations of the method, thereby reducing the need to execute the first and/or second main calculations for extracting the information. The caching involves calculating a first selection identifier value as a function of at least the first selection item, and a second selection identifier value as a function of at least the second selection item and the first result, and storing the first selection identifier value and the first result, and the second selection identifier value and the second result, respectively, as associated objects in a data structure. |
