Data Container Access in a Database System

• US 20130159339A1
• Filed: 12/19/2011
• Published: 06/20/2013
• Est. Priority Date: 12/19/2011
• Status: Abandoned Application

• Current Assignee: SAP AG (SAP SE)
• Original Assignee: SAP AG (SAP SE)
• Inventors: Thomsen, Dirk, Schreter, Ivan, Schroeder, Axel
• Application Number:
  US13/329,552
• Publication Number:
  US 20130159339A1
• Time in Patent Office: Days
• US Class Current: 707/769
• CPC Class Codes: G06F 16/148 File search processing

Abstract

A database system receives a request to access one of a plurality of data containers. Such request includes a file identification (ID) corresponding to the requested data container. Using this file ID, metadata associated with the requested data container is accessed. The metadata is stored in a page of page chain and such metadata identifies a location of the requested data container (so that it can be accessed). Thereafter, the metadata is used to enable access to the requested data container. The file ID in the request can encapsulate a page number and at least one index. This page number identifies a page in the page chain storing the metadata and the index identifies a location within the identified page where the metadata can be found. Related apparatus, systems, techniques and articles are also described.

Claims

1. A method comprising:

receiving, in a database system, a request to access one of a plurality of data containers, the request comprising a file identification (ID) corresponding to the requested data container;

accessing metadata associated with the requested data container based on the file ID, the metadata being stored in a page of a page chain and identifying a location of the requested data container; and

using the metadata to enable access to the requested data container.

2. A method as in claim 1, wherein the file ID encapsulates a page number and at least one index, the page number identifying a page in the page chain storing the metadata and the index identifying a location within the identified page where the metadata can be found.

3. A method as in claim 1, wherein the pages in the page chain have fixed sizes.

4. A method as in claim 1, wherein the pages in the page chain have varying sizes.

5. A method as in claim 1, wherein metadata for particular data containers stored on the pages have varying sizes.

6. A method as in claim 1, wherein each page in the page chain comprises a logical page number.

7. A method as in claim 1, wherein the database system comprises an in-memory database.

8. A computer program product comprising a non-transitory machine-readable medium storing instructions that, when executed by at least one programmable processor, cause the at least one programmable processor to perform operations comprising:

receiving, in a database system, a request to access one of a plurality of data containers, the request comprising a file identification (ID) corresponding to the requested data container;

accessing metadata associated with the requested data container based on the file ID, the metadata being stored in a page of a page chain and identifying a location of the requested data container; and

using the metadata to enable access to the requested data container.

9. A computer program product as in claim 8, wherein the file ID encapsulates a page number and at least one index, the page number identifying a page in the page chain storing the metadata and the index identifying a location within the identified page where the metadata can be found.

10. A computer program product as in claim 8, wherein the pages in the page chain have fixed sizes.

11. A computer program product as in claim 8, wherein the pages in the page chain have varying sizes.

12. A computer program product as in claim 8, wherein metadata for particular data containers stored on the pages have varying sizes.

13. A computer program product as in claim 8, wherein each page in the page chain comprises a logical page number.

14. A computer program product as in claim 8, wherein the database system comprises an in-memory database.

15. A system comprising:

at least one data processor;

memory coupled to the at least one data processor, the memory storing instructions, which when executed, cause the at least one data processor to perform operations comprising

receiving, in a database system, a request to access one of a plurality of data containers, the request comprising a file identification (ID) corresponding to the requested data container;

accessing metadata associated with the requested data container based on the file ID, the metadata being stored in a page of a page chain and identifying a location of the requested data container, wherein the file ID encapsulates a page number and at least one index, the page number identifying a page in the page chain storing the metadata and the index identifying a location within the identified page where the metadata can be found; and

using the metadata to enable access to the requested data container.

16. A system as in claim 15, wherein the pages in the page chain have fixed sizes.

17. A system as in claim 15, wherein the pages in the page chain have varying sizes.

18. A system as in claim 15, wherein metadata for particular data containers stored on the pages have varying sizes.

19. A system as in claim 15, wherein each page in the page chain comprises a logical page number.

20. A system as in claim 15, wherein the database system comprises an in-memory database.