We created tables, dimensions, and a cube; and new tables were automatically created for each dimension and cube. We then created mappings to map data from tables to tables, dimensions, and a cube. What happens if, let's say for example, a table definition is updated after we've defined it and created a mapping or mappings that include it? What if a dimensional object is changed? In that case, what happens to the underlying table? This is what we are going to discuss in this section.
One set of changes that we'll frequently find ourselves making is changes to the data we've defined for our data warehouse. We may get some new requirements that lead us to capture a new data element that we have not captured yet. We'll need to update our staging table to store it and our staging mapping to load it. Our dimension mapping(s) will need to be updated to store the new data element along with the underlying table. We could make manual edits to all the affected objects in our...
