Data access system

• US 7,139,745 B2
• Filed: 05/15/2002
• Issued: 11/21/2006
• Est. Priority Date: 08/12/1999
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nakamura, Lee Evan, Tate, Stewart Eugene
• Primary Examiner(s): Corrielus, Jean M.
• Assistant Examiner(s): HWANG, JOON H
• Application Number:
  US10/145,542
• Publication Number:
  US 20030041055A1
• Time in Patent Office: 1,651 Days
• Field of Search: 707 1- 5, 707 7- 10, 707100-1041, 707200-205, 707/500, 707/513, 709200-203, 711/100, 711/101, 711/154, 711/163, 711/164, 717/100, 717/106, 717/108, 717/114, 717/116, 717/118, 715/500, 715/513
• US Class Current: 1/1
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: Y10S 707/954 Relational
• 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 707/99942 Manipulating data structure, e.g. compression, compaction, compilation
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A TEFP-FEC system provides an efficient technique for storing, updating, locating, and retrieving data. In particular, data may be stored in a persistent, user-defined, shareable in-memory database table. Once this in-memory database table is created and loaded with data, data may be located in the table.

When a search request specifying a number of results to be retrieved from a desired starting point is received, the data is located in an in-memory database table. Then, the specified number of results from a desired starting point are returned.

The data is retrieved from the in-memory database table by retrieving stored descriptors corresponding to search terms in the search request. The stored descriptors are mapped to location information in a header area of an in-memory database table. Using the location information data is retrieved either from a data area of an in-memory database table or from a relational data store.

Furthermore, data that is accessed via an in-memory database table is updated upon receiving an update request. The data that is updated may either be data in a data area of the in-memory database table or may be relational data. When data is updated, a high speed index used to access the in-memory database table is also updated.

Claims

1. A method of updating data in a volatile memory of a computer, comprising:

receiving an update request to update data that is accessed via an in-memory database table stored in the memory, wherein a high speed index contains a stored descriptor describing the data accessed via the in-memory database table, and the in-memory database table has a header area containing location information specifying a location of the data within the in-memory database table, wherein the stored descriptor is mapped to the location information;

updating the data accessed via the in-memory database table; and

updating the stored descriptor in high speed index used to access the in-memory database table in response to updating the data, and

modifying a flag in the header area of the in-memory database table to indicate the update to the data.

2. The method of claim 1, further comprising updating a relational data store.

3. The method of claim 1, further comprising modifying the location information of the header area of the in-memory database table to correspond to the update to the data.

4. The method of claim 1, wherein the in-memory database table is a persistent in-memory database table that remains in memory until a user specifies removal of said in-memory database table.

5. The method of claim 1, wherein the in-memory database table is a persistent in-memory database table in which the updated data remains after the updated data is accessed by a first user and is available for access by a second user.

6. An apparatus for updating data, comprising:

a computer having a memory and connected to a data store, the volatile memory containing an in-memory database table;

one or more computer programs, executed by the computer, for receiving an update request to update data that is accessed via the in-memory database table stored in the memory and updating the data accessed via the in-memory database table, wherein the in-memory database table has a header containing location information specifying a location of the data within the in-memory database table and a flag to indicate the update to the in-memory database table; and

a high speed index having an stored descriptor describing the data accessed via the in-memory database table, the stored descriptor being mapped to the location information, wherein the stored descriptor is updated and the flag is modified in response to updating the data.

7. The apparatus of claim 6, further comprising updating a relational data store.

8. The apparatus of claim 6, further comprising modifying the location information of the header area of the in-memory database table to correspond to update to the in-memory database table.

9. The apparatus of claim 6, wherein the in-memory database table is a persistent in-memory database table that remains in memory until a user specifies removal of said in-memory database table.

10. The apparatus of claim 6, wherein the in-memory database table is a persistent in-memory database table in which the updated data remains after the updated data is accessed by a first user and is available for access by a second user.

11. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to update data in a volatile memory of a computer, comprising:

receiving an update request to update data that is accessed via an in-memory database table stored in the memory, wherein a high speed index contains a stored descriptor describing the data accessed via the in-memory database table, and the in-memory database table has a header area containing location information specifying a location of the data within the in-memory database table, wherein the stored descriptor is mapped to the location information;

updating the data accessed via the in-memory database table;

updating the stored descriptor in high speed index used to access the in-memory database table in response to updating the data; and

modifying a flag in the header area of the in-memory database table to indicate the update to the data.

12. The article of manufacture of claim 11, further comprising updating a relational data store.

13. The article of manufacture of claim 11, further comprising modifying location information of the header area of the in-memory database table to correspond to update to the in-memory database table.

14. The article of manufacture of claim 11, wherein the in-memory database table is a persistent in-memory database table that remains in memory until a user specifies removal of said in-memory database table.

15. The article of manufacture of claim 11, wherein the in-memory database table is a persistent in-memory database table in which the updated data remains after the updated data is accessed by a first user and is available for access by a second user.