Operation of Relational Database Optimizers by Inserting Redundant Sub-Queries in Complex Queries

摘要

Methods and systems are provided to facilitate the optimization process of existing relational database managers when processing complex queries. Specialized constraining clauses are inserted in or added to SQL queries, which do not affect the semantics of the queries. This operation causes the RDBMS to partition the query into sub-queries, and to apply a more efficient optimization for each sub-query. A condition in which the execution time of the modified query substantially exceeds that of the original query may indicate a design flaw in the RDBMS query optimizer.