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Unit 10: Multi-dimensional Data Models and Aggregation

notes

is transformed into

From the perspective of a three-dimensional cuboid, the time _y_ axis is transformed from
months to quarters; see the shaded cells in Figure 10.10.

DRILL DOWN Command

The DRILL DOWN command provides a more detailed breakdown of information from lower
in the hierarchy. For instance, if the user currently analyses the number of sold CPU and Printer
units in Europe and U.S.A., it will allows him/her to find details of sales in specific cities in the
U.S.A., i.e., the view.

is transformed into

Again, using a data cube representation, the location (z) axis is transformed from summarisation
by continents to sales for individual cities; see the shaded cells in Figure 10.11.

SLICE and DICE Command

These commands perform selection and projection of the data cube onto one or more user-
specified dimensions.
SLICE allows the user to focus the analysis of the data on a particular perspective from one or
more dimensions. For instance, if the user analyses the number of sold CPU and Printer units in
all combined locations in the first two quarters of 2002, he/she can ask to see the units in the same
time frame in a particular city, say in Los Angeles. The view

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