-------What are the Adv of Star Schema and Snow Flake
Schema?

Answer Posted / vishwamitra

# 1 StarSchema Advantage: Slicing down,performance increase
and
easy to understand the data.


# 2 Star Schema:
Definition: The star schema is the simplest data warehouse
schema. It is called a star schema because the diagram
resembles a star with points radiating from a center.

A single Fact table (center of the star) surrounded by
multiple dimensional tables(the points of the star).
Advantages:

Simplest DW schema
Easy to understand
Easy to Navigate between the tables due to less number of
joins.
Most suitable for Query processing
Disadvantages:
Occupies more space
Highly Denormalized

Snowflake schema:

Definition: A Snowflake schema is a Data warehouse Schema
which consists of a single Fact table and multiple
dimensional tables. These Dimensional tables are
normalized.A variant of the star schema where each
dimension can have its own dimensions.

Advantages:

These tables are easier to maintain
Saves the storage space.
Disadvantages:

Due to large number of joins it is complex to navigate

Starflake schema - Hybrid structure that contains a mixture
of (denormalized) STAR and (normalized) SNOWFLAKE schemas

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