Thursday, May 26, 2011

What is degenerated Dimension?


The fact table in below contains two additional attributes, order_id and order_line_id, which are neither facts nor foreign keys. These columns reference a specific order and the line number within an order respectively. They are dimensional attributes that have been placed in the fact table rather than a dimension table. Although they could have been placed in the order_type table, doing so would have dramatically increased the number of rows in the table. When a dimensional attribute is located in the fact table, it is known as a  degenerate dimension. - By Christopher Adamson




No comments:

Post a Comment