Systems and methods for online transactional data processing

• US 8,700,562 B2
• Filed: 06/10/2005
• Issued: 04/15/2014
• Est. Priority Date: 06/22/2004
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Schmitt, Winfried, Sykora, Radim
• Primary Examiner(s): KUDDUS, DANIEL A
• Application Number:
  US11/149,191
• Publication Number:
  US 20050283492A1
• Time in Patent Office: 3,231 Days
• Field of Search: 707/607, 707/661, 707/999.204
• US Class Current: 707/607
• CPC Class Codes: G06F 16/2358 Change logging, detection, and notification replication G06F16/27
• CPC Class Codes: G06F 16/2365 Ensuring data consistency and integrity

Abstract

An online transactional data processing (OLTP) system is provided that includes a relational database for storing transactional data, an OLTP application program for processing the transactional data, and a change log for storing a set of change documents that describe transformations performed on the transactional data by the OLTP application program. To correct a run of the OLTP application program, the set of change documents is used to re-establish the original state. A re-run of the OLTP application program may produce a new set of change documents in the random access memory (RAM) of the OLTP system. Further, the original set of change documents stored in the change log may be at least partly overwritten by the new set of change documents.

Claims

1. An online transactional processing (OLTP) system, comprising:

a relational database for storing transactional data;

an OLTP application program for processing the transactional data, the OLTP application program generating a set of change documents for a run of the OLTP application program, wherein the set of change documents includes descriptions of transformations performed on the transactional data by the run of the OLTP application program;

a mass storage device for storing the change documents;

means for receiving a request for correction of a previous run of the OLTP application program;

means for reading the set of change documents of the previous run from the mass storage device into a random access memory;

means for inverting the transformations as described by the set of change documents of the previous run;

means for initiating a renewed run of the OLTP application program to create a new set of change documents that are temporarily stored in the random access memory;

means for identifying corresponding change documents of the previous and the renewed run that differ from each other; and

means for overwriting at least a sub-set of the set of change documents of the previous run stored on the mass storage device by at least a sub-set of the new set of new change documents, wherein the means for overwriting overwrites only change documents of the previous run for which a differing corresponding change document of the renewed run is identified.

2. The online transactional data processing system of claim 1, further comprising:

means for generating a key for each change document, and wherein equivalent change documents are identified by the same key.

3. The online transactional data processing system of claim 2, wherein the key is a hash key.

4. The online transactional data processing system of claim 2, wherein the means for generating a key for a change document excludes a portion of the change document from the generation of the key that is affected by the renewed run.

5. The online transactional data processing system of claim 4, wherein the means for generating a key excludes a time or user indication contained in a change document when generating the key.

6. A computer-implemented method of online transactional processing (OLTP), comprising steps performed by a computer of:

storing transactional data in a relational database;

performing a first run of an OLTP application program for processing the transactional data generating a first set of change documents, wherein the first set of change documents include descriptions of transformations performed on the transactional data by the first run of the OLTP application program;

storing the first set of change documents on a mass storage device;

receiving a request for correction of the first run;

reading the first set of change documents from the mass storage device into a random access memory;

inverting the transformations as described by the first set of change documents;

performing the correction of the transactional data;

initiating a second run of the OLTP application program to create a second set of change documents that is temporarily stored in the random access memory;

identifying corresponding change documents of the first and the second run that differ from each other; and

overwriting at least a sub-set of the first set stored on the mass storage device by at least a sub-set of the second set of change documents, wherein only change documents of the first run for which a differing corresponding change document of the second run is identified are overwritten.

7. The method of online transactional data processing of claim 6, further comprising:

generating a key for each change document of the first and second sets stored in the random access memory, wherein equivalent change documents are identified by identical keys; and

comparing only equivalent change documents of the first and second sets, wherein a change document of the first set is overwritten by an equivalent change document of the second set stored in the mass storage device when the equivalent change document of the second set differs from the change document of the first set.

8. The method of online transactional data processing of claim 7, wherein the key is a hash key.

9. The method of online transactional data processing of claim 7, wherein data fields of the set of first and second change documents that are affected by the second run are excluded from the generation of the key.

10. The online transactional data processing method of claim 6, wherein each change document includes a time data field indicative of a time when the change document was created or a user data field indicative of an entity that caused or requested the respective run of the OLTP application program, and the time data field or the user data field is excluded from the generation of the key.

11. A non-transitory computer-readable storage medium comprising program code instructions for executing a method for online transactional processing (OLTP), the method comprising:

storing transactional data in a relational database;

performing a first run of an OLTP application program for processing the transactional data generating a first set of change documents, wherein the first set of change documents include descriptions of transformations performed on the transactional data by the first run of the OLTP application program;

storing the first set of change documents on a mass storage device;

receiving a request for correction of the first run;

reading the first set of change documents from the mass storage device into a random access memory;

inverting the transformations as described by the first set of change documents;

performing the correction of the transactional data;

initiating a second run of the OLTP application program to create a second set of change documents that is temporarily stored in the random access memory;

identifying corresponding change documents of the first and the second run that differ from each other; and

overwriting at least a sub-set of the first set stored on the mass storage device by at least a sub-set of the second set of change documents, wherein only change documents of the first run for which a differing corresponding change document of the second run is identified are overwritten.

12. The non-transitory computer-readable storage medium of claim 11, the method further comprising:

generating a key for each change document of the first and second sets stored in the random access memory, wherein equivalent change documents are identified by identical keys; and

comparing only equivalent change documents of the first and second sets, wherein a change document of the first set is overwritten by an equivalent change document of the second set stored in the mass storage device when the equivalent change document of the second set differs from the change document of the first set.

13. The non-transitory computer-readable storage medium of claim 12, wherein the key is a hash key.

14. The non-transitory computer-readable storage medium of claim 12, wherein data fields of the set of first and second change documents that are affected by the second run are excluded from the generation of the key.

15. The non-transitory computer-readable storage medium of claim 11, wherein each change document includes a time data field indicative of a time when the change document was created or a user data field indicative of an entity that caused or requested the respective run of the OLTP application program, and the time data field or the user data field is excluded from the generation of the key.