Schema Evolution publication categorizer

Among other issues, database evolution includes the necessity of propagating the changes inside and between abstraction levels. There exist several mechanisms in order to carry out propagations from one level to another, that are distinguished on the basis of when and how the changes are performed. The strict mechanism, which implies the immediate realization of modifications, is a time–consuming process. In this paper we propose a solution that is closer to the lazy and logical mechanisms, in which changes are delayed or not finally realized, respectively. This solution makes use of the notion of view. The use of views allows the data not to be changed if it is not necessary and facilitates carrying out changes when required.