What is a Snowflake Schema with Databases and when to use? CompTIA Data Plus Certification Prep.

comptia data + snowflake schema Nov 07, 2023
 What is a Snowflake Schema with Databases and when to use?

A snowflake schema is a logical arrangement of tables in a multidimensional database such that the entity relationship diagram resembles a snowflake shape. 

It is an extension of the star schema, where dimension tables are broken down into subdimensions. Snowflake schemas are commonly used for business intelligence and reporting in OLAP data warehouses, data marts, and relational databases.

Characteristics of a Snowflake Schema

  • Centralized fact table: Like a star schema, a snowflake schema has a central fact table that contains the core transactional data.

  • Normalized dimension tables: Unlike a star schema, where dimension tables are denormalized to improve query performance, snowflake schemas normalize dimension tables by breaking them down into subdimensions. This normalization helps to reduce data redundancy and improve data integrity.

  • Hierarchical relationships: Snowflake schemas can represent complex hierarchical relationships between dimension tables. This is achieved by using foreign keys to link subdimension tables to their parent dimension tables.

Advantages of a Snowflake Schema

  • Improved data integrity: Normalization reduces data redundancy and improves data consistency.

  • Reduced data anomalies: Normalization helps to eliminate data anomalies, which are inconsistencies in the data.

  • Simplified data management: Normalized data is easier to understand and manage, which can reduce the cost of maintaining the database.

Disadvantages of a Snowflake Schema

  • Increased query complexity: Normalized dimension tables can make queries more complex, which can impact query performance.

  • Increased storage requirements: Normalization can increase the storage requirements of the database.

When to Use a Snowflake Schema

Snowflake schemas are a good choice for databases that need to represent complex relationships between data entities and where data integrity is a priority. They are also a good choice for databases that need to support complex queries. However, snowflake schemas can be more difficult to manage than star schemas, and they may not be as efficient for ad-hoc queries.

Here is an example of a snowflake schema:


Fact Table: Sales

SalesID | CustomerID | ProductID | OrderDate | Quantity | SalesAmount

Dimension Tables:


CustomerID | FirstName | LastName | Email


ProductID | ProductName | ProductCategory | UnitPrice


OrderDate | Day | Month | Year


In this example, the Sales fact table is connected to three dimension tables: Customers, Products, and OrderDates. The Customers dimension table is normalized into two subdimension tables: FirstName and LastName. The OrderDates dimension table is normalized into three subdimension tables: Day, Month, and Year.

The CompTIA Data+ exam is an entry-level certification for aspiring data analysts. It is designed for individuals who want to demonstrate their ability to collect, analyze, and interpret data to inform business decisions.

I hope this blog post has convinced you of the value of the CompTIA Data+ certification exam.

If you are interested in a career in data, I encourage you to take the exam and see how it can help you achieve your goals.

Cloud InterviewACE.

The best way to pass the Cloud Computing interviews. Period.

Cloud InterviewACE is an online training program & professional community mentored by industry veteran Joseph Holbrook (“The Cloud Tech Guy“), a pre/post sales guru in cloud. 

Learn to pass the technical and even soft skills interviews from the starting basics to advanced topics covering presales, post sales focused objectives such cloud deployment, cloud architecting, cloud engineering, migrations and more. resume tips, preparation strategy, common mistakes, mock interviews, technical deep-dives, must-know tips, offer negotiation, and more. AWS, GCP and Azure will be covered. 

Find Out more about Cloud InterviewACE from TechCommanders

Fast-track your career now!  

This changes your world, what are you waiting for!

We are TechCommanders…

experts in Next Generation Technology Training. 

TechCommanders is an online training platform for both aspiring and veteran IT professionals interested in next generation IT Skills.
TechCommanders is led by Joseph Holbrook, a highly sought-after technology industry veteran.

TechCommanders offers blended learning which allows the students to learn on demand but with live training. 


Join TechCommanders Today. 

Over 60 Courses and Practice Questions! 

Coaching and CloudINterviewACE

Join TechCommanders

Stay connected with news and updates!

Join our mailing list to receive the latest news and updates from our team.
Don't worry, your information will not be shared.

We hate SPAM. We will never sell your information, for any reason.