Abstract. This report concentrates on the visualization and analysis
of the behavior of query optimizers. In the paper [6] ”Analyzing Plan
Diagrams of Database Query Optimizers” the authors visualize the query
plans and corresponding estimated costs of a SQL-query with variable
parameters in one- or two-dimensional selectivity spaces. Therefore, they
introduce Plan and Cost Diagrams. The authors show that the number
of query plans of each tested commercial database is surprisingly high.
Moreover, they determine a non-motivated fragmentation of the Plan
Diagrams. To improve this situation the authors introduce Reduced Plan
Diagrams which decrease the number of query plans by summarizing the
query plans of Plan Diagrams with limited additional estimated costs.
Finally, the authors state that the assumptions of Parametric Query
Optimization (PQO) do not hold in practice. They suggest the use of
Reduced Plan Diagrams for PQO. [6]

query_optimization_presentation.pdf Query Optimization (Presentation)

query_optimization_report.pdf Query Optimization (Report)