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@inproceedings{DBLP:conf/vldb/Demolombe79,
author = {Robert Demolombe},
editor = {Antonio L. Furtado and
Howard L. Morgan},
title = {Semantic Checking of Questions Expressed in Predicate Calculus
Language},
booktitle = {Fifth International Conference on Very Large Data Bases, October
3-5, 1979, Rio de Janeiro, Brazil, Proceedings},
publisher = {IEEE Computer Society},
year = {1979},
pages = {444-450},
ee = {db/conf/vldb/Demolombe79.html},
crossref = {DBLP:conf/vldb/79},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
Not all predicate calculus WFF correspond to meaningful questions, In order to avoid this problem, +different authors have defined syntactically the WFF classes which are known to be significative. These restrictions are generally more severe than is necessary, and we have defined a much wider class of WFF : the evaluable formula.
We prove that these WFF have a clearly defined sense. Moreover, we can easily test a formula to see if it is evaluable.
Finally, we show how it is possible to deduce from a formula the conditions which have to be fulfilled by the predicate argument validity domains in order to obtain-answers which are not an empty set. We can thus reject questions which have a defined sense but which, in the context of a clearly determined application, cannot have an answer.
Copyright © 1979 by The Institute of Electrical and Electronic Engineers, Inc. (IEEE). Abstract used with permission.
