PROVIDING PARALLEL RESULT STREAMS FOR DATABASE QUERIES

• US 20100198855A1
• Filed: 01/30/2009
• Published: 08/05/2010
• Est. Priority Date: 01/30/2009
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Therber, Andrew D., RANGANATHAN, VENKATESAN N., Zeller, Hansjorg, Sharma, Anoop
• Granted Patent: US 8,666,966 B2
• Time in Patent Office: Days
• US Class Current: 707/764
• CPC Class Codes: G06F 16/24532 of parallel queries
• CPC Class Codes: G06F 16/24568 Data stream processing; Continuous queries
• CPC Class Codes: G06F 16/284 Relational databases

Abstract

A system and method for providing parallel result streams for database queries is provided. The system includes a network including a client, a server, and a database. The client executes an application and sends a query to the server. In response, the server compiles the query to produce a query plan, executes statements in the query plan and sends parallel result streams to the client.

Claims

1. A method for receiving parallel result streams for database queries, comprising:

in a client, establishing an initiator session with a database server;

sending a query from the initiator session to the database server;

receiving, at the initiator session, access to a plurality of top-level nodes in a query plan stored on the database server;

establishing a plurality of consumer sessions on the client;

receiving, at the consumer sessions, a plurality of parallel result streams from the top-level nodes, the parallel result streams including query results for the query; and

sending the query results to a plurality of destinations from the consumer sessions.

2. The method of claim 1, wherein the query includes a desired number of streams, and the number of consumer sessions and the number of top-level nodes is equal to the desired number of streams.

3. The method of claim 1, further comprising:

receiving, at the initiator session, instructions for establishing the consumer sessions from the database server.

4. A computer-readable medium storing instructions for performing the method of claim 1.

5. A method for providing parallel result streams for database queries, comprising:

receiving a query from a client at a database server;

generating a query plan on the database server in response to the query, the query plan including a root node and a plurality of top-level nodes;

providing access to the top-level nodes in the query plan to the client; and

sending a plurality of result streams from the top-level nodes to the client in parallel.

6. The method of claim 5, further comprising:

receiving a desired number of streams from the client;

providing instructions for establishing a plurality of consumer sessions to the client;

wherein the number of consumer sessions and the number of top-level nodes is equal to the desired number of streams.

7. A computer-readable medium storing instructions for performing the method of claim 5.

8. A system for providing parallel result streams for database queries, comprising:

at least one client executing at least one application, the client including a client processor for executing the application and a client storage device for storing instructions for the application;

a server in communication with the client over a network, the server including at least one storage device for storing at least one query plan and a processor for executing a plurality of statements in the query plan; and

a database in communication with the server;

wherein the client is configured to send a query to the server and, in response, the server is configured to compile the query to produce the query plan, to execute the statements in the query plan and to send a plurality of parallel result streams to the client.

9. The system of claim 8, further comprising:

an initiator session on the client for sending the query to the server; and

a plurality of consumer sessions on the client for receiving the parallel result streams from the server.

10. The system of claim 9, further comprising:

a plurality of destinations for receiving a plurality of query results included in the parallel result streams.

11. The system of claim 9, wherein the query plan comprises a root node, a plurality of top-level nodes, and a plurality of lower nodes.

12. The system of claim 11, wherein the consumer sessions receive the parallel results streams from the top-level nodes.

13. The system of claim 11, wherein the initiator session sends the query to the root node.

14. The system of claim 8, wherein the application is a load/extract application and the database is a hash-partitioned parallel database.

15. The system of claim 8, wherein the storage stores instructions for a plurality of processes, a query compiler, and at least one execution engine and the processor executes the processes, the query compiler, and the execution engine, the execution engine for executing a plurality of statements in the query plan.