The algorithm that allows based on the analysis of monitoring historical data to predict the state of the network has been proposed. It is aimed to evaluate the state of the network using the service level indicators Service Level Objectives, SLO. ...

We investigate the implication problem for classes of data dependencies over SQL table definitions. Under Zaniolo's “no information” interpretation of null markers we establish an axiomatization and algorithms to decide the implication problem for the ...

Consider a relation schema with a set of dependency constraints. A fundamental question is what is the minimum space where the possible instances of the schema can be "stored". We study the following model. Encode the instances by giving a function ...

Besides functional dependencies, multivalued dependencies are also important integrity constrains in XML documents. So far, the definitions for multivalued dependencies are oriented to XML documents, rather than schemata. At present, DTD is accepted to ...

Integrity constraints represent a method of ensuring that database updates do not result in data inconsistencies. For business applications in particular, the accuracy of the data is important. Therefore, we need strong guarantees that the information ...

Multivalued dependencies (MVDs) are an important class of relational constraints that is fundamental to relational database design. Reflexivity axiom, complementation rule, and pseudo-transitivity rule form a minimal set of inference rules for the ...

The impact of the list constructor on two important classes of relational dependencies is investigated. Lists represent an inevitable data structure whenever order matters and data is allowed to occur repeatedly. The list constructor is therefore ...

The implication of multivalued dependencies (MVDs) in relational databases has originally been defined in the context of some fixed finite universe (Fagin 1977, Zaniolo 1976). While axiomatisability, implication problem and many design problems have ...

The implication of multivalued dependencies (MVDs) in relational databases has originally been defined in the context of some fixed finite universe (Fagin 1977, Zaniolo 1976). While axiomatisability, implication problem and many design problems have ...

Discovery of multivalued dependencies from database relations is viewed as a search in a hypothesis space defined according to the generalisation relationship among multivalued dependencies. Two algorithms for the discovery of multivalued dependencies ...

This paper uses the tools of information theory to examine and reason about the information content of the attributes within a relation instance. For two sets of attributes X and Y, an information dependency measure (InD measure) characterizes the ...

Nested relations in partitioned normal form (PNF) are an important subclass of nested relations that are useful in many applications. In this paper we address the question of determining when every PNF relation stored under one nested relation scheme ...

A key is simple if it consists of a single attribute. It is shown that if a relation schema is in third normal form and every key is simple, then it is in projection-join normal form (sometimes called fifth normal form), the ultimate normal form with ...

Database design is based on the concept of data dependency, which is the interrelationship between data contained in various sets of attributes. In particular, functional, multivalued and acyclic join, dependencies play an essential role in the design ...

The problem of determining, given a set of multivalued dependencies, whether or not they logically imply a given join dependency is shown to be computationally intractable.

Template dependencies (TD’s) are a class of data dependencies that include multivalued and join dependencies and embedded versions of these. A collection of techniques, examples and results about TD’s are presented. The principal results are: 1) Finite ...

One problem concerning the universal relation assumption is the inability of known methods to obtain a database scheme design in the general case, where the real-world constraints are given by a set of dependencies that includes embedded multivalued ...

A new normal form for relational databases, called domain-key normal form (DK/NF), is defined. Also, formal definitions of insertion anomaly and deletion anomaly are presented. It is shown that a schema is in DK/NF if and only if it has no insertion or ...

We investigate the question of when two database schemes embody the same information. We argue that this question reduces to the equivalence of the sets of fixed points of the project-join mappings associated with the two database schemes in question. ...