Integrity Constraints Revisited: From Exact to Approximate Implication
Integrity constraints such as functional dependencies (FD) and multi-valued dependencies (MVD) are fundamental in database schema design. Likewise, probabilistic conditional independences (CI) are crucial for reasoning about multivariate probability distributions. The implication problem studies whe...
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Format: | Article |
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Logical Methods in Computer Science e.V.
2022-01-01
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Online Access: | https://lmcs.episciences.org/6925/pdf |
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author | Batya Kenig Dan Suciu |
author_facet | Batya Kenig Dan Suciu |
author_sort | Batya Kenig |
collection | DOAJ |
description | Integrity constraints such as functional dependencies (FD) and multi-valued
dependencies (MVD) are fundamental in database schema design. Likewise,
probabilistic conditional independences (CI) are crucial for reasoning about
multivariate probability distributions. The implication problem studies whether
a set of constraints (antecedents) implies another constraint (consequent), and
has been investigated in both the database and the AI literature, under the
assumption that all constraints hold exactly. However, many applications today
consider constraints that hold only approximately. In this paper we define an
approximate implication as a linear inequality between the degree of
satisfaction of the antecedents and consequent, and we study the relaxation
problem: when does an exact implication relax to an approximate implication? We
use information theory to define the degree of satisfaction, and prove several
results. First, we show that any implication from a set of data dependencies
(MVDs+FDs) can be relaxed to a simple linear inequality with a factor at most
quadratic in the number of variables; when the consequent is an FD, the factor
can be reduced to 1. Second, we prove that there exists an implication between
CIs that does not admit any relaxation; however, we prove that every
implication between CIs relaxes "in the limit". Then, we show that the
implication problem for differential constraints in market basket analysis also
admits a relaxation with a factor equal to 1. Finally, we show how some of the
results in the paper can be derived using the I-measure theory, which relates
between information theoretic measures and set theory. Our results recover, and
sometimes extend, previously known results about the implication problem: the
implication of MVDs and FDs can be checked by considering only 2-tuple
relations. |
first_indexed | 2024-04-25T01:32:57Z |
format | Article |
id | doaj.art-04e2ad0d45d34300a58907bffcd4e253 |
institution | Directory Open Access Journal |
issn | 1860-5974 |
language | English |
last_indexed | 2024-04-25T01:32:57Z |
publishDate | 2022-01-01 |
publisher | Logical Methods in Computer Science e.V. |
record_format | Article |
series | Logical Methods in Computer Science |
spelling | doaj.art-04e2ad0d45d34300a58907bffcd4e2532024-03-08T10:36:53ZengLogical Methods in Computer Science e.V.Logical Methods in Computer Science1860-59742022-01-01Volume 18, Issue 110.46298/lmcs-18(1:5)20226925Integrity Constraints Revisited: From Exact to Approximate ImplicationBatya KenigDan SuciuIntegrity constraints such as functional dependencies (FD) and multi-valued dependencies (MVD) are fundamental in database schema design. Likewise, probabilistic conditional independences (CI) are crucial for reasoning about multivariate probability distributions. The implication problem studies whether a set of constraints (antecedents) implies another constraint (consequent), and has been investigated in both the database and the AI literature, under the assumption that all constraints hold exactly. However, many applications today consider constraints that hold only approximately. In this paper we define an approximate implication as a linear inequality between the degree of satisfaction of the antecedents and consequent, and we study the relaxation problem: when does an exact implication relax to an approximate implication? We use information theory to define the degree of satisfaction, and prove several results. First, we show that any implication from a set of data dependencies (MVDs+FDs) can be relaxed to a simple linear inequality with a factor at most quadratic in the number of variables; when the consequent is an FD, the factor can be reduced to 1. Second, we prove that there exists an implication between CIs that does not admit any relaxation; however, we prove that every implication between CIs relaxes "in the limit". Then, we show that the implication problem for differential constraints in market basket analysis also admits a relaxation with a factor equal to 1. Finally, we show how some of the results in the paper can be derived using the I-measure theory, which relates between information theoretic measures and set theory. Our results recover, and sometimes extend, previously known results about the implication problem: the implication of MVDs and FDs can be checked by considering only 2-tuple relations.https://lmcs.episciences.org/6925/pdfcomputer science - databases |
spellingShingle | Batya Kenig Dan Suciu Integrity Constraints Revisited: From Exact to Approximate Implication Logical Methods in Computer Science computer science - databases |
title | Integrity Constraints Revisited: From Exact to Approximate Implication |
title_full | Integrity Constraints Revisited: From Exact to Approximate Implication |
title_fullStr | Integrity Constraints Revisited: From Exact to Approximate Implication |
title_full_unstemmed | Integrity Constraints Revisited: From Exact to Approximate Implication |
title_short | Integrity Constraints Revisited: From Exact to Approximate Implication |
title_sort | integrity constraints revisited from exact to approximate implication |
topic | computer science - databases |
url | https://lmcs.episciences.org/6925/pdf |
work_keys_str_mv | AT batyakenig integrityconstraintsrevisitedfromexacttoapproximateimplication AT dansuciu integrityconstraintsrevisitedfromexacttoapproximateimplication |