Query Plan Analysis Of Alternative Plans Using Robustness Mapping

Abstract

Computer-implemented and associated operating methods evaluate robustness of a query plan by measuring performance with regard to a range of runtime conditions and producing a map of relative performance of the given query plan when compared with alternative plans for a range of conditions. The computer-implemented system comprises logic that evaluates the selected query plan in comparison to multiple alternative query plans in a predetermined range of runtime conditions that include data characteristics. The logic produces a set of performance measurements and analyzes the measured performance to map performance of the selected query plan in comparison to performance of one or more alternative query plans.

1 - 15 . (canceled) 
     
     
         16 . A computer-implemented system comprising:
 a processor; and   logic stored in memory, the logic executable by the processor to evaluate a selected query plan in comparison to alternative query plans over a predetermined range of runtime conditions including data characteristics, wherein to evaluate comprises to:
 produce performance measurements of the selected query plan and the alternative query plans over the predetermined range of runtime conditions; and 
 analyze the performance measurements to map performance of the selected query plan in comparison to performance of at least one alternative query plan of the alternative query plans over the predetermined range of runtime conditions. 
   
     
     
         17 . The system according to claim  15 , wherein the performance comprises anticipated performance on a database system. 
     
     
         18 . The system according to claim  15 , wherein to map performance generates a performance map. 
     
     
         19 . The system according to  claim 18 , wherein the predetermined range of runtime conditions comprise a resource availability, wherein a first axis of the performance map comprises the resource availability, and a second axis of the performance map comprises cardinality. 
     
     
         20 . The system according to claim  15 , wherein to evaluate the selected query plan in comparison to alternative query plans comprises to generate a marked performance map through the predetermined range of runtime conditions, wherein marking is indicative of performance of the selected query plan in comparison to at least one of the alternative query plans under runtime conditions of the predetermined range of runtime conditions. 
     
     
         21 . The system according to claim  15 , wherein to evaluate the selected query plan in comparison to alternative query plans comprises to generate a marked performance map, and wherein marking is indicative of regions of the predetermined range of runtime conditions where the selected query plan degrades a predetermined amount when compared to a best alternative query plan of the alternate query plans. 
     
     
         22 . The system according to claim  15 , wherein the data characteristics comprise cardinality, and the runtime conditions comprise available memory. 
     
     
         23 . The system according to claim  15 , wherein the logic comprises a query optimizer that generates via the processor the plurality of alternative query plans for a query. 
     
     
         24 . The system according to claim  15 , wherein the logic via the processor generates the alternative query plans for a query to be evaluated under a set of predetermined runtime resource conditions. 
     
     
         25 . The system according to  claim 24 , wherein the logic via the processor executes the query to be evaluated using the alternative query plans with a range of predetermined runtime resource conditions forming a query plan/resource condition coordinate set, the logic via the processor comparing performance of the selected query plan to performance of a best performing alternative query plan of the alternate query plans for each coordinate set and generating a performance map as a function of the query plan/resource condition coordinate set, the performance map indicative of comparison of the selected query plan to the best performing alternative query plan of the alternative query plans over the query plan/resource condition coordinate set. 
     
     
         26 . The system according to claim  15 , comprising an interface to receive a query, a target query plan, and a set of runtime resource conditions to be evaluated, wherein the logic via the processor iterates through the predetermined range of runtime conditions comprising to iterate running the query for sets of runtime conditions under the selected query plan and alternative query plans. 
     
     
         27 . The system according to  claim 26 , wherein to iterate running the query comprises running the query under the sets of runtime conditions for the selected query plan and alternative query plans while collecting the alternative query plans generated by a query optimizer. 
     
     
         28 . The system according to  claim 26 , wherein to iterate running the query comprises measuring and collecting performance results of the running of the query runs iteratively through the selected query plan and the alternative query plans under the sets of runtime conditions. 
     
     
         29 . The system according to  claim 26 , wherein the logic via the processor compares performance of the selected query plan to performance of a determined best alternative query plan for selected sets of runtime conditions. 
     
     
         30 . A computer-implemented method comprising:
 evaluating, via a processor, a selected query plan in comparison to alternative query plans over a predetermined range of runtime conditions including data characteristics, the evaluating comprising:
 producing performance measurements of the selected query plan and the alternative query plans over the predetermined range of runtime conditions; and 
 analyzing the performance measurements to map performance of the selected query plan in comparison to performance of at least one alternative query plan of the alternative query plans over the predetermined range of runtime conditions. 
   
     
     
         31 . The method according to  claim 30 , wherein the evaluating comprises generating a marked performance map through the predetermined range of runtime conditions, wherein marking is indicative of performance of the selected query plan in comparison to at least one of the alternative query plans under sets of runtime conditions of the predetermined range of runtime conditions. 
     
     
         32 . The method according to  claim 30 , wherein the evaluating comprises generating a marked performance map, wherein marking is indicative of regions of the predetermined range of runtime conditions where the selected query plan degrades a predetermined amount when compared to a best alternative query plan of the alternate query plans. 
     
     
         33 . The method according to  claim 30 , comprising generating via the processor the alternative query plans via a query optimizer, and wherein to map performance comprises to generate a performance map. 
     
     
         34 . A non-transitory computer-readable medium comprising instructions that direct a processor to:
 evaluate a selected query plan in comparison to alternative query plans over a predetermined range of runtime conditions comprising data characteristics;   produce performance measurements of the selected query plan and the alternative query plans over the predetermined range of runtime conditions; and   analyze the performance measurements to map performance of the selected query plan in comparison to performance of at least one alternative query plan of the alternative query plans over the predetermined range of runtime conditions, wherein to map the performance comprises to generate a performance map.   
     
     
         35 . The non-transitory computer-readable medium of  claim 34 , wherein the performance map comprises a marked performance map, wherein marking is indicative of regions of the predetermined range of runtime conditions where the selected query plan degrades a predetermined amount when compared to a best alternative query plan of the alternate query plans.