However, the drilling operations become almost trivial. For the same reason, there are benefits in keeping the complete dimensional structure in the same table. One of the particular advantages to using depth is that dimensional navigation is simpler. Depending upon how you physically implement dimensions, using depth may also allow you to relax the requirement that member names be unique within the dimension, so that uniqueness can be limited to a single level in a single hierarchy. Depth Depth is also a way of identifying location.
Depth is counted from the top down.
Hence, height G1 represents the highest level of aggregation. What Chen would call a strong entity. One of the disadvantages of relational databases is that there is no clean way to deal with a dimension that is not uniform with respect to height and depth. If we think of these as tree structures, relational databases are not good at dealing with unbalanced trees. Again, some but not all, multi-dimensional databases deal with unbalanced trees very well.