They are 3 types of database schema they are
- Star
- Snowflake
- Starflake
Star schema:
In star schema fact table will be directly linked with all
dimension tables. The star schema’s dimensions are denormalized with each
dimension being represented by a single table. In a star schema a central fact
table connects a number of individual dimension tables.
Snowflake:
The snowflake schema is an extension of the star schema,
where each point of the star explodes into more points. In a star schema, each
dimension is represented by a single dimensional table, whereas in a snowflake
schema, that dimensional table is normalized into multiple lookup tables, each
representing a level in the dimensional hierarchy. In snow flake schema fact
table will be linked directly as well as there will be some intermediate
dimension tables between fact and dimension tables.
Star flake:
A hybrid structure that contains a mixture of
star(denormalized) and snowflake(normalized) schema’s.
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