In the DW world, the word “dimension” is overloaded — changes meaning depending on context. Here is an example. On a certain date, a customer walks into a store and buys a product. This example has four dimensions (date, customer, store, product) and one fact (sales). So a typical Kimball star would look like: A … Read more
Mythology I always thought that databases should be denormalized for reading, as it is done for OLAP database design, and not exaggerated much further 3NF for OLTP design. There’s a myth to that effect. In the Relational Database context, I have re-implemented six very large so-called “de-normalised” “databases”; and executed over eighty assignments correcting problems … Read more
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