Open Issues and Research Directions

In the previous chapters we have proposed a formal framework for the definition and representation of time granularities, we have investigated applications in temporal database design and in querying temporal databases under multiple views, and we have shown how reasoning with temporal constraints is affected when the constraints are given in terms of arbitrary granularities. The theoretical issues addressed in this book, as well as their applications, are not long established topics; they are still the subject of ongoing research. The purpose of this last chapter is to illustrate some of the problems we encountered while developing these theories and that we believe deserve further investigation. We also illustrate some of the applications that we could not investigate in detail in the book, but that we believe could greatly benefit from our results on granularity representation and reasoning.