Star Schema |
Snowflake Schema |
Simple Database Design. |
Very Complex Database Design. |
De-normalized Data structure. |
Normalized Data Structure. |
Query also run faster. |
Query runs slower comparatively star schema. |
It contains one fact table surrounded by
dimension tables. |
One fact table surrounded by dimension table
which are in turn surrounded by dimension table |
It is easy to understand and provides optimal disk usage |
It uses smaller disk space. |
Only single join creates the relationship
between the fact table and any dimension tables. |
It requires many joins to fetch the data. |
Single Dimension table contains aggregated
data. |
Data Split into different Dimension Tables. |
High level of data redundancy |
Very low-level data redundancy |
Cube processing is faster. |
Cube processing might be slow because of the
complex join. |
Hierarchies for the dimensions are stored in
the dimensional table. |
Hierarchies are divided into separate
tables. |
Offers higher performing queries using Star
Join Query Optimization. Tables may be connected with multiple dimensions. |
It is represented by
centralized fact table which unlikely connected with multiple dimensions. |
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