Difference between Star Schema and Snowflake Schema.

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 Difference between Star Schema and Snowflake Schema

• Star Schema is a multi-dimension model where each of its disjoint dimensions is represented in a single table.

• Snow-flake is a normalized multi-dimension schema when each disjoint dimension is represented in multiple tables.

• Star schema can become a snow-flake

• Both star and snowflake schemas are dimensional models; the difference is in their physical implementations.

• Snowflake schemas support ease of dimension maintenance because they are more normalized.

• Star schemas are easier for direct user access and often support simpler and more efficient queries.

• It may be better to create a star version of the snowflaked dimension for presentation to the users.


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