Historical data for in memory data warehouse

• US 9,773,048 B2
• Filed: 09/12/2013
• Issued: 09/26/2017
• Est. Priority Date: 09/12/2013
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP SE
• Inventors: Sarferaz, Siar
• Primary Examiner(s): Vo, Truong
• Application Number:
  US14/025,597
• Publication Number:
  US 20150074038A1
• Time in Patent Office: 1,475 Days
• CPC Class Codes: G06F 16/2477 Temporal data queries
• CPC Class Codes: G06F 16/254 Extract, transform and load [ETL] procedures, e.g. ETL data flows in data warehouses
• CPC Class Codes: G06F 16/283 Multi-dimensional databases or data warehouses, e.g. MOLAP or ROLAP

Abstract

A method includes processing a transaction on an in memory database where data being processed has a validity time, updating a time dependent data view responsive to the transaction being processed to capture time validity information regarding the data, and storing the time validity information in a historization table to provide historical access to past time dependent data following expiration of the validity time.

Claims

1. A method comprising:

processing, by a computer system, a transaction on a table stored in an in memory database wherein data being processed as part of the transaction has a validity time;

determining, by the computer system, that a virtual data management view exists which is based on the table stored in the in memory database;

determining, by the computer system, that the data being processed has an effect on the virtual data management view;

updating, by the computer system, the virtual data management view responsive to the transaction being processed to capture time validity information regarding the data;

determining, by the computer system, that the virtual data management view comprises an activated keep history flag, wherein the keep history flag is only activated if time-dependent data is maintained for the virtual data management view; and

based on determining the virtual data management view comprises an activated keep history flag, storing, by the computer system, the time validity information in a historization table with the same structure as the virtual data management view to provide historical access to past time dependent data following expiration of the validity time.

2. The method of claim 1 wherein the historization table is an insert only table.

3. The method of claim 1 wherein the time validity information comprises from—

to information regarding the data.

4. The method of claim 1 and further comprising providing in memory data warehouse functions against the transaction data.

5. The method of claim 1 wherein storing the time validity information comprises storing a delta of a tuple with a single timestamp.

6. The method of claim 1 wherein storing the time validity information comprises storing a full tuple including additional information useable to determine a time span of its validity.

7. The method of claim 1 and further comprising associating every relation stored in a column-oriented layout with an additional write-optimized insert-only differential buffer.

8. The method of claim 7 wherein inserts, updates, and delete operations are performed on the differential buffer.

9. The method of claim 8 and further comprising performing a merge process on the differential buffer and a main store that stores the data.

10. The method of claim 1, wherein the virtual data management view is stored in an in memory database system over the table stored in the in memory database.

11. The method of claim 1, wherein the virtual data management view is a predefined view.

12. A non-transitory computer-readable medium comprising instructions stored thereon that are executable by one or more processors to perform operations comprising:

processing a transaction on a table stored in an in memory database wherein data being processed as part of the transaction has a validity time;

determining that a virtual data management view exists which is based on the table stored in the in memory database;

determining that the data being processed has an effect on the virtual data management view;

updating the virtual data management view responsive to the transaction being processed to capture time validity information regarding the data;

determining that the virtual data management view comprises an activated keep history flag, wherein the keep history flag is only activated if time-dependent data is maintained for the virtual data management view; and

based on determining the virtual data management view comprises an activated keep history flag, storing the time validity information in a historization table with the same structure as the virtual data management view to provide historical access to past time dependent data following expiration of the validity time.

13. The non-transitory computer-readable medium of claim 12, wherein the historization table is an insert only table.

14. The computer readable storage device of claim 12 wherein the time validity information comprises from—

to information regarding the data.

15. The non-transitory computer-readable medium of claim 12, wherein storing the time validity information comprises storing a delta of a tuple with a single timestamp.

16. The non-transitory computer-readable medium of claim 12, the operations further comprising associating every relation stored in a column-oriented layout with an additional write-optimized insert-only differential buffer.

17. The non-transitory computer-readable medium of claim 16, wherein inserts, updates, and delete operations are performed on the differential buffer.

18. The non-transitory computer-readable medium of claim 17, wherein the operations further comprises, comprise:

performing a merge process on the differential buffer and a main store that stores the data.

19. An in memory data warehouse comprising:

one or more processors; and

a non-transitory computer-readable medium comprising instructions stored thereon that are executable by the one or more processors to perform operations comprising;

processing a transaction on a table stored in an in memory database wherein data being processed as part of the transaction has a validity time;

determining that a virtual data management view exists which is based on the table stored in the in memory database;

determining that the data being processed has an effect on the virtual data management view;

updating the virtual data management view responsive to the transaction being processed to capture time validity information regarding the data;

determining that the virtual data management view comprises an activated keep history flag, wherein the keep history flag is only activated if time-dependent data is maintained for the virtual data management view; and

based on determining the virtual data management view comprises an activated keep history flag, storing the time validity information in a historization table with the same structure as the virtual data management view to provide historical access to past time dependent data following expiration of the validity time.

20. The in memory data warehouse of claim 19 wherein the operations further comprise:

associating every relation stored in a column-oriented layout with an additional write-optimized insert-only differential buffer, wherein inserts, updates, and delete operations are performed on the differential buffer and;

performing a merge process on the differential buffer and a main store that stores the data.