Adjusting an amount of data logged for a query based on a change to an access plan

• US 20060106786A1
• Filed: 11/12/2004
• Published: 05/18/2006
• Est. Priority Date: 11/12/2004
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: International Business Machines Corporation
• Inventors: Day, Paul Reuben, Muras, Brian Robert, Ryg, Anne Marie
• Granted Patent: US 7,493,304 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2455 Query execution
• 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 707/99943 Generating database or data structure, e.g. via user interface

Abstract

A method, apparatus, system, and signal-bearing medium that, in an embodiment, save a problem record associated with a query to a log if the query encountered a problem. The amount of data in the record is increased if an access plan associated with the query has changed within a threshold amount of time and decreased if the access plan has not changed. In various embodiments, the problem may be that the query executes longer than a historical average for the query, the query executes longer than a threshold, or the query encounters a functional error. In an embodiment, a benchmark record associated with the query is also saved to the log, the problem record is compared to the benchmark record, and the difference is presented. In various embodiments, an oldest record is periodically removed from the log, or an oldest record is removed from the log if the associated query has more than a threshold number of records in the log. In this way, the amount of data in the log may be reduced and determining the source of query performance problems may be more easily determined.

Claims

1. A method comprising:

determining whether data needs to be logged for a query, wherein the query is performed based on an access plan; and

adjusting an amount of the data saved to a log based on whether the access plan for the query has been changed within a threshold amount of time if the determining is true.

2. The method of claim 1, wherein the adjusting further comprises:

increasing the amount of the data saved to the log if the access plan has been changed within the threshold amount of time.

3. The method of claim 1, wherein the adjusting further comprises:

decreasing the amount of the data saved to the log if the access plan has not been changed with the threshold amount of time.

4. The method of claim 1, wherein the determining further comprises:

determining whether the query runs longer than a historical average for the query.

5. An apparatus comprising:

means for determining whether a problem record needs to be saved to a log for a query, wherein the query is performed based on an access plan; and

means for adjusting an amount of the data saved to the problem record in the log based on whether the access plan for the query has been changed within a threshold amount of time if the means for determining is true; and

means for saving a benchmark record for the query in the log.

6. The apparatus of claim 5, further comprising:

means for comparing the benchmark record to the problem record; and

means for presenting a difference based on the means for comparing.

7. The apparatus of claim 5, further comprising:

means for periodically removing an oldest record from the log.

8. The apparatus of claim 5, further comprising:

means for removing an oldest record from the log if the query has more than a threshold number of records in the log.

9. A signal-bearing medium encoded with instructions, wherein the instructions when executed comprise:

saving a benchmark record associated with a query to a log if benchmarking is enabled;

saving a problem record associated with the query to the log if benchmarking is not enabled and the query encountered a problem; and

comparing the benchmark record to the problem record.

10. The signal-bearing medium of claim 9, wherein the problem comprises:

the query executes longer than a historical average for the query

11. The signal-bearing medium of claim 9, wherein the problem comprises:

the query executes longer than a threshold.

12. The signal-bearing medium of claim 9, wherein the problem comprises:

the query encounters a functional error.

13. A computer system comprising:

a processor; and

a storage device encoded with instructions, wherein the instructions when executed on the processor comprise;

saving a benchmark record associated with a query to a log if benchmarking is enabled,

saving a problem record associated with the query to the log if benchmarking is not enabled and the query encountered a problem, wherein the saving further comprises adjusting an amount of data in the problem record based on whether an access plan for the query has changed within a threshold amount of time, and

comparing the benchmark record to the problem record.

14. The computer system of claim 13, wherein the problem comprises:

the query executes longer than a historical average for the query

15. The computer system of claim 13, wherein the problem comprises:

the query executes longer than a threshold.

16. The computer system of claim 13, wherein the problem comprises:

the query encounters a functional error.

17. A method for configuring a computer, comprising:

configuring the computer to determine whether data needs to be logged for a query, wherein the query is performed based on an access plan; and

configuring the computer to adjust an amount of the data saved to a log based on whether the access plan for the query has been changed within a threshold amount of time if the determining is true.

18. The method of claim 17, wherein the configuring the computer to adjust further comprises:

configuring the computer to increase the amount of the data saved to the log if the access plan has been changed within the threshold amount of time.

19. The method of claim 17, wherein the configuring the computer to adjust further comprises:

configuring the computer to decrease the amount of the data saved to the log if the access plan has not been changed with the threshold amount of time.

20. The method of claim 17, wherein the configuring the computer to determine further comprises:

configuring the computer to determine whether the query runs longer than a historical average for the query.