Book Image

Data Modeling with Snowflake

By : Serge Gershkovich
5 (2)
Book Image

Data Modeling with Snowflake

5 (2)
By: Serge Gershkovich

Overview of this book

The Snowflake Data Cloud is one of the fastest-growing platforms for data warehousing and application workloads. Snowflake's scalable, cloud-native architecture and expansive set of features and objects enables you to deliver data solutions quicker than ever before. Yet, we must ensure that these solutions are developed using recommended design patterns and accompanied by documentation that’s easily accessible to everyone in the organization. This book will help you get familiar with simple and practical data modeling frameworks that accelerate agile design and evolve with the project from concept to code. These universal principles have helped guide database design for decades, and this book pairs them with unique Snowflake-native objects and examples like never before – giving you a two-for-one crash course in theory as well as direct application. By the end of this Snowflake book, you’ll have learned how to leverage Snowflake’s innovative features, such as time travel, zero-copy cloning, and change-data-capture, to create cost-effective, efficient designs through time-tested modeling principles that are easily digestible when coupled with real-world examples.
Table of Contents (24 chapters)
1
Part 1: Core Concepts in Data Modeling and Snowflake Architecture
8
Part 2: Applied Modeling from Idea to Deployment
14
Part 3: Solving Real-World Problems with Transformational Modeling

Mandatory columns as NOT NULL constraints

When defining attributes for an entity, the question of which ones are mandatory and which are optional inevitably arises. As with most modeling decisions, the answer depends on the business context more than any technical database property. The same attribute, for example, the email address for CUSTOMER, may be mandatory for an online store but optional for a brick-and-mortar retailer. In the latter case, not having an email address means missing sales announcements, while in the former, it may mean being unable to access the website.

When moving from a conceptual model to a physical Snowflake design, mandatory columns can be defined through the NOT NULL constraint. The NOT NULL constraint is declared inline next to the corresponding column and does not need to be given a name. Due to this, it is not possible to declare NOT NULL constraints out of line.

The format for adding a NOT NULL constraint to a column is as follows:

<col1_name...