Approach for publishing data in a relational database system
US6502093B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2002 |
| Grant date | Dec 31, 2002 |
| Priority date | — |
| Expiry date | Mar 14, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99935
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus are provided for implementing a content-based publish-and-subscribe system in a relational database system. A subscriber may request for messages by using a query language supported by the database server. The queries are then used as subscription rules for determining whether an incoming message is to be sent to the subscriber. Evaluation of incoming messages against subscription rules involves a two-tier process. The first tier involves filtering out all the subscription rules that could not possibly apply to the incoming message. The second tier involves further evaluation of the incoming message, if needed, to determine which subscribers are to receive the incoming message. In another aspect of the embodiment, in cases where the publisher is the relational database system itself, queries that request for messages are not stored as subscription rules because publication of the messages is implicit. In this situation, a query is received from a client that is written in a query language supported by the database system. The query is a request for data stored in the database system that satisfies the query. A detection is made that the data stored in the dat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.