Consistent Query Answering in Data Warehouses
A Data Warehouse (DW) is a data repository that organizes and physically integrates data from multiple sources under special kinds of schemas. A DW is composed by a set of dimensions that reflect the way the data is structured, and the facts that correspond to quantitative data related with the dimensions. A dimension schema is a hierarchical graph of categories. A dimension instance is strict if every element of the dimension has a unique ancestor element in each of the ancestor categories.