ADDITION AND PROCESSING OF CONTINUOUS SQL QUERIES IN A STREAMING RELATIONAL DATABASE MANAGEMENT SYSTEM

• US 20090228434A1
• Filed: 03/05/2009
• Published: 09/10/2009
• Est. Priority Date: 03/06/2008
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Krishnamurthy, Saileshwar, Hoyer, Morten, Thombre, Neil, Li, Wing Hang, Conway, Neil
• Granted Patent: US 8,812,487 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/24532 of parallel queries
• CPC Class Codes: G06F 16/24568 Data stream processing; Continuous queries
• CPC Class Codes: G06F 16/2471 Distributed queries

Abstract

Systems, methods, and media are disclosed herein that can be embodied in a traditional Relational Database Management System (RDBMS) in order to transform it into a Streaming Relational Database Management System (SRDBMS). An SRDBMS may provide functionality such as to manage and populate streams, tables, and archived stream histories and support the evaluation of continuous queries on streams and tables. Both continuous and snapshot queries support the full spectrum of the industry standard, widely used, Structured Query Language. The present technology can support a high number of concurrent continuous queries using a scalable and efficient shared query evaluation scheme, support on-the-fly addition of continuous queries into a mechanism that implements the shared evaluation scheme, reuse RDBMS modules such as relational operators and expression evaluators, and visualize results of continuous queries in real time

Claims

1. A method for managing a data stream, comprising:

generating an iterator-model subplan from an iterator-model plan;

assigning a continuous-query operator to the iterator-model subplan; and

assigning an adapter to the iterator-model subplan.

2. The method of claim 1, wherein the adapter comprises a new leaf node to the iterator-model subplan.

3. The method of claim 1, further comprising:

receiving a continuous-query tuple; and

providing the continuous-query tuple to a parent of the continuous-query operator.

4. A method for managing a data stream, comprising:

providing a data tuple to a stream-to-relation operator;

assigning a control tuple to the data tuple.

5. The method of claim 4, wherein the control tuple includes a timestamp.

6. The method of claim 4, wherein assigning the control tuple to the data tuple includes identifying the trigger of a window edge.

7. The method of claim 6, further comprising:

routing the data tuple to a downstream operator; and

routing the control tuple to the downstream operator after routing the data tuple.

8. A method for providing data for display based on a continuous query, comprising:

receiving a result of a continuous query to a data stream;

receiving a request based on a parameter; and

providing for display the result of the continuous query based on the request.