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Steps in designing Star Schema


                                                                                                                                                                      
Steps in designing Star Schema
• Identify a business process for analysis (like sales).
• Identify measures or facts (sales dollar).
• Identify dimensions for facts (product dimension, location dimension, time dimension, organization dimension).
• List the columns that describe each dimension.(region name, branch name, region name).
• Determine the lowest level of summary in a fact table(sales dollar).
Important aspects of Star Schema & Snow Flake Schema
• In a star schema every dimension will have a primary key.
• In a star schema, a dimension table will not have any parent table.
• Whereas in a snow flake schema, a dimension table will have one or more parent tables.
• Hierarchies for the dimensions are stored in the dimensional table itself in star schema.
• Whereas hierarchies are broken into separate tables in snow flake schema. These hierachies helps to drill down the data from topmost hierarchies to the lowermost hierarchies.

Comments

  1. TejutejuJune 20, 2018 at 4:17 PM

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