Abstract:
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The aim of this paper is to obtain advantages for integrity constraint
checking in bitemporal deductive databases, analyzing the temporal
integrity constraint behaviour. First at all, a new taxonomy of temporal
integrity constraints is introduced to achieve a better understanding of
why constraints are required and a best way to define them using first
order logic. In order to meet these goals, we have studied temporal
integrity constraint taxonomies existing on the temporal database area
and other deeply related areas such as multiversion databases. These
works have been adapted and further developed to cover the scope of
bitemporal deductive databases.
Before checking, we study the transaction behaviour, introducing the
concept of coherent transaction. This allows us to reject transactions
that are not coherent, without more information requirements.
For integrity constraint checking in bitemporal deductive databases, we
derive a set of transition rules for each temporal integrity constraint.
Then, Standard Linear Deduction with Negation as Failure Resolution is
used to verify that a transaction does not violate any constraint before
the transaction is allowed to commit. The set of transition rules
obtained is very large; therefore, a carefully analysis of the integrity
constraints using the taxonomy introduced above drastically reduces the number of rules. Finally, the paper concludes with an example of the application of this new reduced set of transition rules for integrity
constraint checking in bitemporal deductive databases. |