Data Mining: Current Status and Directions. What is Data Mining?. Data mining (also called knowledge discovery in databases)
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Creating Multi-dimensional data warehouses
In order to reduce the number of joins that must be performed, data is reformatted into ‘fact’ tables. Fact tables typically consist of many foreign keys
Very similar to the snowflake schema, can you tell what this schema lets us see that the snowflake did not?
Example: Consider analyzing sales based on the dimensions of Route, Source, and Time. The number of rows in each view is given in Millions.
Route, Source, Time
Materialization of all views would require roughly 19.1 Million rows
Selective materialization in this case can reduce the number of stored rows by 12 Million
Assume that ‘Part’ can be further partitioned into ‘size’ and ‘color’, ‘Customer’ can be partitioned into ‘Individual’, ‘State’, and ‘Country’
More Generalized Descriptions