System and method for a data dictionary cache in a distributed system

• US 7,421,437 B2
• Filed: 11/10/2003
• Issued: 09/02/2008
• Est. Priority Date: 11/10/2003
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Hammerich, Reiner, Tsesis, Michael, Hoeft, Kerstin
• Primary Examiner(s): Alam; Hosain T
• Assistant Examiner(s): Ahn; Sangwoo
• Application Number:
  US10/704,924
• Publication Number:
  US 20050102277A1
• Time in Patent Office: 1,758 Days
• Field of Search: 707 1- 10, 707100-1041
• US Class Current: 1/1
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 67/288 Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level
• CPC Class Codes: H04L 67/303 Terminal profiles
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing

Abstract

A system and method to provide a data dictionary cache in a distributed system is disclosed. An application server may include a data dictionary broker agent to provide an interface between an underlying data dictionary and an application. The application server may also include one or more data dictionary caches to provide efficient access to frequently requested system information.

Claims

1. A computer-implemented method comprising:

receiving a request for system information, wherein the system information is associated with a data type, wherein the data type includes a scalar data type and a complex data type, wherein the scalar data type and the complex data type are organized hierarchically, the scalar data type including a single data object having an integer or a character, the complex data type including multiple data objects having one or more of structure data types, list data types, and tree data types;

referencing a plurality of data dictionary cache at an application level to obtain the data type associated with the system information;

determining whether the data type is stored in one or more of the plurality of data dictionary cache, wherein determining is preformed based on a cache management policy to perform operations relating to reading, storing, and maintaining information of the plurality of data dictionary cache;

selecting a data dictionary cache from the plurality of data dictionary cache at the application level, if the data dictionary cache includes the data type;

obtaining the data type from the data dictionary cache having the data type;

obtaining the data type from a data dictionary at a data access level, if the data type is not found at the plurality of data dictionary cache, and creating a new data dictionary cache at the application layer to store the data type obtained from the data dictionary; and

providing the requested system information via the data type.

2. The method of claim 1, wherein the data type comprises one or more of a scalar data type and a complex data type.

3. The method of claim 1, wherein the data type comprises a markup language-based data type including an Extensible Markup Language (XML) data type.

4. The method of claim 1, wherein the application level comprises an application server, the application server including a Web application server.

5. The method of claim 4, wherein the Web application server comprises a Java 2 Enterprise Edition (J2EE) application server.

6. An application server comprising:

a data medium having a plurality of data dictionary cache at an application level; and

a data dictionary server in communication with the plurality of data dictionary cache, the data dictionary server having an agent to

receive a request for system information, wherein the system information is associated with a data type, wherein the data type includes a scalar data type and a complex data type, wherein the scalar data type and the complex data type are organized hierarchically, the scalar data type including a single data object having an integer or a character, the complex data type including multiple data objects having one or more of structure data types, list data types, and tree data types,

reference the plurality of data dictionary cache to obtain the data type associated with the system information,

determine whether the data type is stored in one or more of the plurality of data dictionary cache, wherein determining is preformed based on a cache management policy to perform is relating to reading, storing, and maintaining information of the plurality of data dictionary cache,

select a data dictionary cache from the plurality of data dictionary cache at the application level, if the data dictionary cache includes the date type,

obtain the data type from the data dictionary cache having the data type,

obtain the data type from a data dictionary at a data access level, if the data type is not found at the plurality of data dictionary cache, and create a new data dictionary cache at the application layer to store the data type obtained from the data dictionary, and

provide the requested system information via the data type.

7. The application server of claim 6, wherein the application server is coupled to one or more application servers over a network via a network interface.

8. The application server of claim 6, wherein the application server comprises a Web application server.

9. The application server of claim 8, wherein the Web application server comprises a Java 2 Enterprise Edition (J2EE) application server.

10. The application server of claim 6, wherein the data type comprise a markup language-based data type including an Extensible Markup Language (XML) data type.

11. A system comprising:

a client to send a request for system information, wherein the system information is associated with a data type; and

a server coupled with the client, the server to

receive the request from the client,

reference a plurality of data dictionary cache at an application level to obtain the data type associated with the system information, wherein the data type includes a scalar data type and a complex data type, wherein the scalar data type and the complex data type are organized hierarchically, the scalar data type including a single data object having an integer or a character, the complex data type including multiple data objects having one or more of structure data types, list data types, and tree data types

determine whether the data type is stored in one or more of the plurality of the data dictionary cache, wherein determining is preformed based on a cache management policy to perform operations relating to reading, storing, and maintaining information of the plurality of data dictionary cache,

select a data dictionary cache from the plurality of data dictionary cache at the application level, if the data dictionary cache includes the date type,

obtain the data type from the data dictionary cache having the data type,

obtain the data type from a data dictionary at a data access level, if the data type is not found at the plurality of data dictionary cache, and create a new data dictionary cache at the application layer to store the data type obtained from the data dictionary, and

provide the requested system information via the data type to the client.

12. The system of claim 11, wherein the data type comprises a markup language-based data type including an Extensible Markup Language (XML) data type.

13. The system of claim 11, wherein the server comprises an application server, the application includes a Web application server.

14. The system of claim 13, wherein the Web application server comprises a Java 2 Enterprise Edition (J2EE) application server.

15. An article of manufacture comprising a machine-readable medium having instructions which when executed causes a machine to:

receive a request for system information, wherein the system information is associated with a data type, wherein the data type includes a scalar data type and a complex data type, wherein the scalar data type and the complex data type are organized hierarchically, the scalar data type including a single data object having an integer or a character, the complex data type including multiple data objects having one or more of structure data types, list data types, and tree data types;

reference a plurality of data dictionary cache at an application level to obtain the data type associated with the system information;

determine whether the data type is stored in one or more of the plurality of the data dictionary cache, wherein determining is preformed based on a cache management policy to perform operations relating to reading, storing, and maintaining information of the plurality of data dictionary cache;

select a data dictionary cache from the plurality of data dictionary cache at the application level, if the data dictionary cache includes the date type;

obtain the data type from the data dictionary cache having the data type;

obtain the data type from a data dictionary at a data access level, if the data type is not found at the plurality of data dictionary cache, and create a new data dictionary cache at the application layer to store the data type obtained from the data dictionary; and

provide the requested system information via the data type.

16. The article of manufacture of claim 15, wherein the instructions which when further executed, cause the machine to

provide the data type to a client in response to the request received from the client.