We address the problem of efficiently evaluating target functional dependencies (fds) in the Data Exchange (DE) process. Target fds naturally occur in many DE scenarios, including the ones in Life Sciences in which multiple source relations need to be structured under a constrained target schema. However, despite their wide use, target fds’ evaluation is still a bottleneck in the state-of-the-a...

We investigate the complexity of computing an optimal repair of an inconsistent database, in the case where integrity constraints are Functional Dependencies (FDs). We focus on two types of repairs: an optimal subset repair (optimal S-repair) that is obtained by a minimum number of tuple deletions, and an optimal update repair (optimal U-repair) that is obtained by a minimum number of value (ce...

Constraints that are defined by tables of allowed tuples of assignments are common in constraint programming. In this paper we present an approach to reformulating table constraints of large arity into a conjunction of lower arity constraints. Our approach exploits functional dependencies. We study the complexity of finding reformulations that either minimize the memory size or arity of a const...

During the life of a database, systematic and frequent violations of a given constraint may suggest that the represented reality is changing and thus the constraint should evolve with it. In this paper we propose a method and a tool to (i) find the functional dependencies that are violated by the current data, and (ii) support their evolution when it is necessary to update them. The method reli...

The notion of user preference in database modeling has recently received much attention in advanced applications, such as personalization of e-services, since it captures the human wishes on querying and managing data. The paradigm of preference-driven choices in the real world requires new semantic constraints in modelling. In this paper, we assume preference constraints can be defined over da...

We present a novel approach to the design of schemas appropriate for data analysis; we call such schemas “analysis contexts”. Roughly speaking, an analysis context is a set of paths with common origin, in which the nodes are attributes and the edges are functional dependencies. Our main contributions are (a) an algorithm for generating all analysis contexts embodied in a set of attributes and a...

The extraction of functional dependencies is a fundamental activity in the database design recovery process which is part of on an overall information systems reverse engineering effort. Existing algorithms for this task are computationally expensive and appear to be infeasible if applied to large legacy database instances, e.g., their performance deteriorated when number of attributes or/and i...