Estimating Compilation Time of a Query Optimizer

A query optimizer compares alternative plans in its search space to find the best plan for a given query. Depending on the search space and the enumeration algorithm, optimizers vary in their compilation time and the quality of the execution plan they can generate. This paper describes a compilation time estimator that provides a quantified estimate of the optimizer compilation time for a given query. Such an estimator is useful for automatically choosing the right level of optimization in commercial database systems. In addition, compilation time estimates can be quite helpful for mid-query reoptimization, for monitoring the progress of workload analysis tools where a large number queries need to be compiled (but not executed), and for judicious design and tuning of an optimizer. Previous attempts to estimate optimizer compilation complexity used the number of possible binary joins as the metric and overlooked the fact that each join often translates into a different number of join p...

• Type: Conference
• Year: 2003
• Where: SIGMOD
• Authors: Ihab F. Ilyas, Jun Rao, Guy M. Lohman, Dengfeng Gao, Eileen Tien Lin
• Keywords: Compilation Time Estimates, Database, Optimizer Compilation Time, Query Compilation Time, SIGMOD 2003