OPTIMIZING PARAMETERIZED QUERIES IN A RELATIONAL DATABASE MANAGEMENT SYSTEM
First Claim
1. A system that facilitates dynamic plan generation, comprising:
- a parameter distribution component that receives a parameterized query and selects a representative sample of parameter values in view of an entire parameter space;
a costing analysis component that calculates costs of plan options corresponding to the selected representative sample of parameter values, the plan options set forth execution of queries; and
a plan generation component that generates a dynamic plan that incorporates more than one plan option as a function of the calculated costs.
2 Assignments
0 Petitions
Accused Products
Abstract
Parameterized queries are optimized by a transformational optimizer. The optimizer produces a dynamic plan that embeds multiple plan options that may be selected to execute a particular query. Parameter distribution improves query execution efficiency and performance by exploring a sample parameter space representative of the parameter values actually used. The dynamic plans can be simplified while maintaining an acceptable level of optimality by reducing the number of plan options. The reduction is achieved by eliminating switch unions to alternatives that are close in cost. Both approaches of parameter space exploration and dynamic plan generation are deeply integrated into the query optimizer.
-
Citations
20 Claims
-
1. A system that facilitates dynamic plan generation, comprising:
-
a parameter distribution component that receives a parameterized query and selects a representative sample of parameter values in view of an entire parameter space; a costing analysis component that calculates costs of plan options corresponding to the selected representative sample of parameter values, the plan options set forth execution of queries; and a plan generation component that generates a dynamic plan that incorporates more than one plan option as a function of the calculated costs. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method that facilitates dynamic plan generation, comprising the following acts:
-
calculating costs associated with a plurality of query execution plan options that provide support for query execution; and generating a dynamic query execution plan that integrates at least two query execution plan options based on the calculated costs. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A system that facilitates dynamic plan generation, comprising:
-
means for designating a representative sample of parameter values that represent an entire parameter space; means for determining costs of plan options that correspond to the designated representative sample of parameter values, the plan options facilitate query execution; and means for creating a dynamic plan that embeds at least two plan options based on the determined costs of plan options. - View Dependent Claims (19, 20)
-
Specification