
18 1.2 Data Modeling for Data Warehouses
Figure 1.9 simply contains another fact entity or another subset of the
data contained in the normalized entity relationship structure in Figures 1.6
and 1.7. It is quite conceivable that the two fact entity sets in Figures 1.8
and 1.9 should be merged into a single entity, separating used, damaged,
scrapped, and lost containers by an appropriate type column.
There could be a small problem with the fact entity shown in Figure 1.9.
Damaged, scrapped, and lost containers could either be a fact entity or part
of the CONTAINER dimension. This decision would depend on exactly
how often containers are damaged, scrapped ...