Method and system for executing a database query

• US 20040205057A1
• Filed: 01/20/2004
• Published: 10/14/2004
• Est. Priority Date: 04/08/2003
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: International Business Machines Corporation
• Inventors: Zeng, Pucheng, Nobles, Acie E. Jr., Hutchison, Grant L.
• Granted Patent: US 7,475,055 B2
• Time in Patent Office: Days
• US Class Current: 707/3
• CPC Class Codes: G06F 16/2471 Distributed queries
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99939 Privileged access

Abstract

For a database management system installed in a data processing system, the database management system for managing a database having partitions for storing table data based on a partitioning schema, in which each partition has an associated partition identifier, and in which the database has database catalog information associated therewith, a method for executing a query against the database is disclosed. The method includes identifying a partition identifier in accordance with the partitioning schema, selecting the partition identifier based on the contents of the query and the database catalog information, and executing the query against the identified partition. The method improves the execution of queries while minimizing the consumption of network resources.

Claims

1. A method for executing a query against a database, wherein the database includes partitions for storing table data based on a partitioning schema with each partition associated with a partition identifier and database catalog information associated with the database, the method comprising:

(a) identifying a partition identifier in accordance with the partitioning schema;

(b) selecting the partition identifier based upon the contents of the query and the database catalog information; and

(c) executing the query against the identified partition.

2. The method of claim 1, wherein step (b) further includes:

(b.1) storing the database catalog information in a database catalog cache.

3. The method of claim 2, wherein step (b.1) further includes:

(b.1.1) building a subset of the database catalog; and

(b.1.2) storing the subset of the database catalog in the catalog cache.

4. The method of claim 1, wherein step (b) further includes:

(b.1) resolving the partition identifier.

5. The method of claim 4, wherein step (c) further includes:

(c.1) executing the query based upon the identified partition identifier.

6. The method of claim 4, wherein step (b) further includes:

(b.2) forwarding the identified partition identifier to a client application requesting table data.

7. A database management system for executing a query against a database, wherein the database includes partitions for storing table data based on a partitioning schema with each partition associated with a partition identifier and database catalog information associated with the database, the method comprising:

a schema-lookup module to identify a partition identifier in accordance with the partitioning schema;

a partition-router module to select the partition identifier based upon the contents of the query and the database catalog information; and

a data-manager module to execute the query against the identified partition.

8. The system of claim 7, wherein the partition-router module includes:

a catalog-cache module to store a portion of the database catalog information in a database catalog cache.

9. The system of claim 8, wherein the catalog-cache module includes:

a build-cache module to build a subset of the database catalog; and

a store-cache module to store the subset of the database catalog in the catalog cache.

10. The system of claim 7, wherein the partition-router module includes:

a connection module to resolve the partition identifier.

11. The system of claim 10, wherein the data-manager module includes:

an execution module to execute the query based upon the identified partition identifier.

12. The system of claim 10, wherein the partition-router module includes:

a client-coordinator module to forward the identified partition identifier to a client application requesting table data.

13. A program product apparatus having a computer readable medium with computer program logic recorded thereon for executing a query against a database, wherein the database includes partitions for storing table data based on a partitioning schema with each partition associated with a partition identifier and database catalog information associated with the database, said program product apparatus comprising:

a schema-lookup module to identify a partition identifier in accordance with the partitioning schema;

a partition-router module to select the partition identifier based upon the contents of the query and the database catalog information; and

a data-manager module to execute the query against the identified partition.

14. The program product of claim 13, wherein the partition-router module includes:

a catalog-cache module to store a portion of the database catalog information in a database catalog cache.

15. The program product of claim 14, wherein the catalog-cache module includes:

a build-cache module to build a subset of the database catalog; and

a store-cache module to store the subset of the database catalog in the catalog cache.

16. The program product of claim 13, wherein the partition-router module includes:

a connection module to resolve the partition identifier.

17. The program product of claim 16, wherein the data-manager module includes:

an execution module to execute the query based upon the identified partition identifier.

18. The program product of claim 16, wherein the partition-router module includes:

a client-coordinator module to forward the identified partition identifier to a client application requesting table data.