Thursday, November 3, 2011

Snowflake Schema in Data Warehouse

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.


  1. The biggest advantage of snowflake schema is improved query performance.
  2. Reduces dimension table size.


  1. Additional maintenance efforts needed due to the increase number of lookup or detail tables

1 comment:

Albina N muro said...

Star and snowflake schemas are most commonly found in dimensional data warehouses and data marts where speed of data retrieval is more important. survival warehouse food supplies