Junk dimensions

1. Describe slowly changing dimensions. What are the three types? Explain each type very briefly.

2. Compare and contrast type 2 and type 3 slowly changing dimensions.

3. What are junk dimensions? Are they necessary in a data warehouse?

1. Discuss data granularity in a data warehouse.

2. Name any three advantages of the STAR schema. Can you think of any disadvantages of the STAR schema?

In a STAR schema to track the shipments for a distribution company, the following dimension tables are found: (1) time, (2) customer ship-to, (3) ship-from, (4) product, (5) type of deal, and (6) mode of shipment. Review these dimensions and list the possible attributes for each of the dimension tables. Also, designate a primary key for each table.

You are the data design specialist on the data warehouse project team for a manufacturing company. Design a STAR schema to track the production quantities. Production quantities are normally analyzed along the business dimensions of product, time, parts used, production facility, and production run. State your assumptions.

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