System and method for performing a data uniqueness check in a sorted data set

• US 7,752,181 B2
• Filed: 11/08/2004
• Issued: 07/06/2010
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Sinha, Bipul, Ganesh, Amit, Klein, Jonathan
• Primary Examiner(s): Jalil; Neveen Abel
• Assistant Examiner(s): RADTKE, MARK A
• Application Number:
  US10/984,113
• Publication Number:
  US 20060122963A1
• Time in Patent Office: 2,066 Days
• Field of Search: 707/100
• US Class Current: 707/692
• CPC Class Codes: G06F 16/22 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/2365 Ensuring data consistency and integrity

Abstract

Embodiments of the present invention include a method for performing a data uniqueness check in a set of sorted data blocks comprising accessing data to be inserted into the set of sorted data blocks, determining a proper data block of the set of sorted data blocks for which the data to be inserted should be located based on a first sorting key. The method further includes examining the proper data block for an existing data entry and if the proper data block is empty, the method further includes inserting the data to be inserted into the proper data block of the set of sorted data blocks.

Claims

1. A method for performing data uniqueness checking in sorted data sets, comprising:

storing sorted data blocks in a physical storage unit in a sorted layout structure;

accessing data for physical insertion in said physical storage unit;

determining a particular data block of said sorted data blocks in which to physically insert said accessed data in said physical storage unit using said sorted layout structure and a first sorting key;

examining said particular data block in said physical storage unit for presence of an existing data entry;

when said particular data block is empty, physically inserting said accessed data into said particular data block in said sorted layout structure of said physical storage unit;

when said particular data block comprises an existing entry, determining whether said particular data block in said sorted layout structure of said physical storage unit is pinned or unpinned; and

in response to determining that said particular data block is unpinned, throwing an error indicating said accessed data is a duplicate of said existing entry of said sorted data blocks.

2. The method as recited in claim 1 further comprising:

in response to determining that said particular data block is pinned, determining if said particular data block is either committed or rolled back.

3. The method as recited in claim 2 further comprising:

in response to determining that said particular data block is committed, generating a uniqueness error indicating said accessed data is a duplicate of said sorted data blocks.

4. The method as recited in claim 2 further comprising:

in response to determining that said particular data block is rolled back, inserting said accessed data into said particular data block of said sorted data blocks.

5. The method as recited in claim 1 further comprising:

determining that said particular data block is associated with deleted data;

accessing an undo log pointer associated with said deleted data;

accessing a data block pointed to by said undo log pointer wherein said data block comprises said deleted data; and

determining a value of said deleted data.

6. The method as recited in claim 5 further comprising:

in response to determining that said value of said deleted data is different than a value of said accessed data, inserting said accessed data into said particular data block of said sorted data blocks.

7. The method as recited in claim 5 further comprising:

in response to determining that said value of said deleted data is equal to a value of said accessed data, determining whether said deleted data comprises said first sorting key.

8. The method as recited in claim 7 further comprising:

in response to determining that said deleted data comprises a second sorting key that is different from said first sorting key, inserting said accessed data into said particular data block of said sorted data blocks.

9. The method as recited in claim 1 wherein said stored data blocks comprise sorted hash clusters.

10. A computer system for performing data uniqueness checking in sorted data sets, comprising:

means for storing stored data blocks in said physical storage unit in a sorted layout structure;

means for accessing data for physical insertion in said physical storage unit;

means for determining a particular location in said sorted data blocks in which to physically insert said accessed data in said physical storage unit using said sorted layout structure and a first sorting key;

means for examining said particular location in said physical storage unit for presence of an existing entry;

means for physically inserting said accessed data in said particular location in said sorted layout structure of said physical storage unit; and

means for throwing an error in response to a determination by said means for examining said particular location that said particular data block comprises an existing entry and that said existing entry is unpinned.

11. The computer system as recited in claim 10 further comprising:

means for determining if an existing entry of said particular location is either pinned or unpinned.

12. The computer system as recited in claim 11 further comprising:

means for determining if a pinned data block is either committed or rolled back.

13. The computer system as recited in claim 10 wherein said sorted data blocks comprise sorted hash clusters.

14. The computer system as recited in claim 10 wherein said means for examining is configured to identify deleted data associated with said particular location in said sorted data blocks.

15. The computer system as recited in claim 14 further comprising:

means for accessing an undo log pointer associated with said deleted data.

16. The computer system as recited in claim 15 further comprising:

means for determining a value of said deleted data.

17. The computer system as recited in claim 16 further comprising:

means for comparing said value of said deleted data to a value of an existing entry of said particular location in said sorted data blocks.

18. The computer system as recited in claim 14 further comprising:

means for comparing a second sorting key associated with said deleted data to said first sorting key.

19. A computer readable storage medium comprising executable instructions stored therein which, when executed in a processing system, causes the system to implement a method of performing data uniqueness checking in sorted data sets, comprising:

instructions that cause the system to store sorted data blocks in a physical storage unit in a sorted layout structure;

instructions that cause the system to access data for physical insertion in said physical storage unit a particular data block of said sorted data blocks in which to physically insert said accessed data in said physical storage unit using said sorted layout structure and a first sorting key;

instructions that cause the system to examine said particular data block in said physical storage unit for presence of an existing data entry;

instructions that cause the system to, when said particular data block is empty, physically insert said accessed data into said particular data block in said sorted layout structure of said physical storage unit; and

instructions that cause the system to, when said particular data block comprises an existing entry, determine whether said particular data block in said sorted layout structure of said physical storage unit is pinned or unpinned; and

instructions that cause the system to, in response to determining that said particular data block is unpinned, throw an error indicating said accessed data is a duplicate of said existing entry of said sorted data blocks.

20. The computer readable storage medium as recited in claim 19 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said particular data block is pinned, determine if said particular data block is either committed or rolled back.

21. The computer readable storage medium as recited in claim 20 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said particular data block is committed, generate a uniqueness error indicating said accessed data is a duplicate of said existing entry of said sorted data blocks.

22. The computer readable storage medium as recited in claim 20 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said particular data block is rolled back, insert said accessed data into said particular data block of said sorted data blocks.

23. The computer readable storage medium as recited in claim 19 wherein said executable instructions further comprise:

instructions that cause the system to determine that said particular data block is associated with deleted data;

instructions that cause the system to access an undo log pointer associated with said deleted data;

instructions that cause the system to access a data block pointed to by said undo log pointer wherein said data block comprises said deleted data; and

instructions that cause the system to determine a value of said deleted data.

24. The computer readable storage medium as recited in claim 23 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said value of said deleted data is different than a value of said accessed data, insert said accessed data into said particular data block of said sorted data blocks.

25. The computer readable storage medium as recited in claim 23 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said value of said deleted data is equal to a value of said accessed data, determine whether said deleted data comprises said first sorting key.

26. The computer readable storage medium as recited in claim 25 wherein said executable instructions further comprise:

instructions that cause the system to, in response to determining that said deleted data comprises a second sorting key that is different from said first sorting key, insert said accessed data into said particular data block of said sorted data blocks.

27. The computer readable storage medium as recited in claim 19 wherein said sorted data blocks comprise sorted hash clusters.