Please use this identifier to cite or link to this item:
http://hdl.handle.net/1942/716
Title: | Simulation of the nested relational algebra by the flat relational algebra, with an application to the complexity of evaluating powerset algebra expressions | Authors: | VAN DEN BUSSCHE, Jan | Issue Date: | 2001 | Publisher: | Elsevier | Source: | Theoretical Computer Science, 254(1-2). p. 363-377 | Abstract: | Paredaens and Van Gucht proved that the flat relational algebra has the same expressive power as the nested relational algebra, as far as queries over flat relations and with flat results are concerned. We provide a new, very direct proof of this fact using a simulation technique. Our technique is also applied to partially answer a question posed by Suciu and Paredaens regarding the complexity of evaluating powerset algebra expressions. Specifically, we show that when only unary flat relations are into play, any powerset algebra expression is either equivalent to a nested algebra expression, or its evaluation will produce intermediate results of exponential size. | Document URI: | http://hdl.handle.net/1942/716 | ISSN: | 0304-3975 | e-ISSN: | 1879-2294 | DOI: | 10.1016/S0304-3975(99)00301-1 | ISI #: | 000167791900013 | Category: | A1 | Type: | Journal Contribution | Validations: | ecoom 2002 |
Appears in Collections: | Research publications |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
simulation.pdf | 273.93 kB | Adobe PDF | View/Open |
SCOPUSTM
Citations
20
checked on Sep 2, 2020
WEB OF SCIENCETM
Citations
19
checked on Sep 26, 2024
Page view(s)
88
checked on Jun 14, 2023
Download(s)
192
checked on Jun 14, 2023
Google ScholarTM
Check
Altmetric
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.