# Galaxy Schema

Essentially, Galaxy schema can be derived as a collection of star schemas interlinked and completely normalized to avoid redundancy and inaccuracy of data. It is also called **Fact Constellation Schema.**

Let's combine the above two Star Schemas.

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#### Advantages

* Minimum or no redundancy as a result of Normalization.
* This is a flexible Schema, considering the complexity of the system.

#### Disadvantages

* Working on this schema is tedious, as Schema and database systems' complexity makes it more intricate.
* Data retrieval is done with multi-level joins combined with conditional expressions.
* The number of levels of normalization is expected, depending on the depth of the given database.
