Fact constellation schema

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What is fact constellation schema? For each star schema it is possible to construct fact constellation schema(for example by splitting the original star schema into more star schemes each of them describes facts on another level of dimension hierarchies). The fact constellation architecture contains multiple fact tables that share many dimension tables. 

The main shortcoming of the fact constellation schema is a more complicated design because many variants for particular kinds of aggregation must be considered and selected. Moreover, dimension tables are still large.

Data Warehouse schema architecture Star schema Snowflake schema