Key
Differences Between Star and Snowflake Schema
1.
Star schema contains just one dimension table for one dimension entry
while there may exist dimension and sub-dimension table for one entry.
2.
Normalization is used in snowflake
schema which eliminates the data redundancy. As against, normalization is not
performed in star schema which results in data redundancy.
3.
Star schema is simple, easy to
understand and involves less intricate queries. On the contrary, snowflake
schema is hard to understand and involves complex queries.
4.
The data model approach used in a
star schema is top-down whereas snowflake schema uses bottom-up.
5.
Star schema uses a fewer number of
joins. On the other hand, snowflake schema uses a large number of joins.
6.
The space consumed by star schema
is more as compared to snowflake schema.
7.
The time consumed for executing a
query in a star schema is less. Conversely, snowflake schema consumes more time
due to the excessive use of joins.
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