snowflake VS star schema

	Snowflake Schema	Star Schema
Query Performance:	More foreign keys-and hence more query execution time	Less no. of foreign keys and hence lesser query execution time
Normalization:	Has normalized tables	Has De-normalized tables
Type ofDatawarehouse:	Good to use for small datawarehouses/datamarts	Good for large datawarehouses
Joins:	Higher number of Joins	Fewer Joins
Dimension table:	It may have more than onedimension table for each dimension	Contains only single dimension table for each dimension
When to use:	When dimension table is relatively big in size, snoflaking is better as it reduces space.	When dimension table contains less number of rows, we can go forStar schema.
Ease of maintenance/change:	No redundancy and hence more easy to maintain and change	Has redundant data and hence less easy to maintain/change
Ease of Use:	More complex queries and hence less easy to understand	Less complex queries and easy to understand