System and method for computing running and moving sequence functions in a database system
US6317738A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1999 |
| Grant date | Nov 13, 2001 |
| Priority date | — |
| Expiry date | Mar 26, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99935
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A database query compiler and compilation method has special facilities for compiling a query that includes one or more of a predefined set of running and moving sequence functions. The compiler converts the query into a predefined normalized form suitable for compilation using a running and moving function normalizer. The running and moving function normalizer converts each running and moving sequence function in the set into a corresponding ordered set of one or more executable statements, which include at least one Offset sequence function that accesses data in an auxiliary field of a row of a table. An offset sequence function compiler, compiles each Offset sequence function, Offset(argument, index), in the normalized database query into a compiled set of instructions, including instructions for storing and reading the auxiliary fields to and from a buffer that is separate from the table. The buffer is preferably stored in volatile, main memory. As a result, when the Offset sequence function is executed, information from a previous is accessed without having to change the cursor position for the table.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.