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  1. Data Warehousing Concepts
  2. Dimensional Modelling

Snowflake Schema

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Last updated 2 years ago

Snowflake is an extension of the Star Schema.

Dimension tables are further normalized and can have their categories.

One or more lookup tables can describe each dimension table. Normalization is recursive until the model is fully normalized.

Check dim_store, dim_product, and dim_time and compare with Star Schema.

Check the Sales Order Schema

Advantages

Better data quality. Less disk space is used compared to Star Schema.

Disadvantages

The major disadvantage is too many tables to join. Poorly written queries result in a decrease in performance significantly.