DIMENSIONS IN DATA WAREHOUSES (DWS) ARE MODELED USING A HIERARCHICAL SCHEMA OF CATEGORIES. A DIMENSION SHOULD SATISFY A SET OF CONSTRAINTS TO ENSURE THAT QUERIES CAN BE ANSWERED EFFICIENTLY USING PRE-COMPUTED ANSWERS. FOR MANY REASONS A DIMENSION MIGHT BECOME INCONSISTENT AND THERE MIGHT BE SEVERAL WAYS TO FIX IT. IN ORDER TO REPRESENT THIS UNCERTAINTY, WE INTRODUCE THE CONCEPT OF EXTENDED DIMENSIONS, THAT IS, DIMENSIONS WHERE CATEGORIES CONTAIN SETS OF ELEMENTS WHICH ALLOW TO REPRESENT AMBIGUITY. IN THIS ARTICLE WE FORMALIZE EXTENDED DIMENSIONS AND A SUITABLE WAY TO ANSWER QUERIES FROM THEM.