Technical Reports (CIS)

Document Type

Technical Report

Date of this Version

February 1994


University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-94-05.


We show that a form of divide and conquer recursion on sets together with the relational algebra expresses exactly the queries over ordered relational databases which are NC-computable. At a finer level, we relate k nested uses of recursion exactly to ACk, k ≥ 1. We also give corresponding results for complex objects.



Date Posted: 25 July 2007