PARAMETER-SENSITIVE PLANS FOR STRUCTURAL SCENARIOS

• US 20080313131A1
• Filed: 06/15/2007
• Published: 12/18/2008
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Galindo-Legaria, Cesar A., Prakash, Naveen, Friedman, Marc T., Ismert, Erik, Joshi, Milind Madhukar
• Granted Patent: US 7,933,894 B2
• Time in Patent Office: Days
• US Class Current: 707/2
• CPC Class Codes: G06F 16/24542 Plan optimisation

Abstract

Systems and methods that generate specialized plans for compiling SQL queries. A plan generator component scans the query representation for parameter sensitive predicates and evaluates each predicate individually based on the parameter values. Accordingly, queries can be identified not only based on their structures, but also based on their parameter conditions. The specialized plans are more efficient for particular values, wherein queries that employ such values are optimally executed.

Claims

1. A computer implemented system comprising the following computer executable components:

a plan generator component that scans representation of a query for parameter sensitive predicates; and

a specialized plan(s) created based on the parameter sensitive predicates to execute the query.

2. The computer implemented system of claim 1 further comprising dispatch expressions that match query values.

3. The computer implemented system of claim 1 further comprising a procedure cache that stores the specialized plans.

4. The computer implemented system of claim 3 further comprising a lookup component that searches a procedure cache for specialized plans.

5. The computer implemented system of claim 3 further comprising a query component that extracts query predicates for the plan generator.

6. The computer implemented system of claim 3 further comprising an artificial intelligence component that facilitates generation of the specialized plans.

7. The computer implemented system of claim 3 further comprising dispatch expressions that returns a key as to which specialized plan to execute.

8. The computer implemented system of claim 2 further comprising a guard expression that evaluates a validity of pairing a plan with the query.

9. A computer implemented method comprising the following computer executable acts:

forming a specialized compilation plan based on parameter sensitive predicates of a received query; and

executing the query based on the received query.

10. The computer implemented method of claim 9 further comprising scanning for the parameter sensitive predicates.

11. The computer implemented method of claim 9 further comprising constructing dispatch expressions that return keys for the specialized query plan.

12. The computer implemented method of claim 9 further comprising identifying the query based on parameter sensitive value.

13. The computer implemented method of claim 9 further comprising determining whether query has been previously cached.

14. The computer implemented method of claim 9 further comprising generating specialized compilation plans based on inferring state of a system associated therewith.

15. The computer implemented method of claim 9 further comprising retrieving a prior cached specialized compilation plan.

16. The computer implemented method of claim 12 further comprising forming a Boolean constant from the set {true, false, NULL}.

17. The computer implemented method of claim 16 further comprising eliminating Boolean constants.

18. The computer implemented method of claim 12 further comprising verifying the query is a parameterized query.

19. The computer implemented method of claim 18 further comprising extracting query predicates from the query.

20. A computer implemented system comprising the following computer executable components:

means for generating specialized plans to execute a query; and

means for retrieving the specialized plans from a cache.