The method is more general than other methods that deal with the issue of propagating data-independent selections and projections through recursion at compile time. The development of this method is the result of work with the modest goal of designing an algorithm that can deal with a wide variety of queries and extend all other known algorithms. This goal is achieved. The work is described carefully and thoroughly. Necessary background is concisely presented.
Related work is analyzed, compared, and credited.
The authors' patience in bringing this work to press is noteworthy. The paper includes extensive references to the period from 1986 to 1988, so the intervening revisions were worthwhile and currency is maintained. The Digital Library is published by the Association for Computing Machinery.