How to set up relations between tables in unity catalog tables

[NarenderKumar]

We are using unity catalog.

Is there a way to set up relations in unity catalog tables like key column relations, 1 to many, many to 1.

Can we also generate ER diagrams if we are able to set up these relations.

[Kaniz_Fatma]

Hi @NarenderKumar, 

• Unity Catalog allows you to define relationships between tables using key columns. Here are the common types of relationships you can set up:
  • One-to-Many (1:N): In this relationship, one record in the primary table corresponds to multiple records in the related table. For example, a customer can have multiple orders.
  • Many-to-One (N:1): This is the reverse of the above. Multiple records in the primary table link to a single record in the related table. For instance, multiple orders belong to the same customer.
  • Many-to-Many (N:N): This type involves an intermediary table that connects two other tables. It’s useful when multiple records in both tables can be related to each other. For example, students and courses in a university system.
• To set up these relations, you’ll need to define foreign keys in your tables. These keys link the primary key of one table to the corresponding column in another table.
• Unity Catalog doesn’t directly provide an automatic ER diagram generation feature. However, you can create ER diagrams manually using external tools or by visualizing the relationships in your tables.
• Here’s how you can approach it:
  • Catalog Explorer: Use the Entity Relationship Diagram (ERD) view in Catalog Explorer. It displays primary key and foreign key relationships between tables in a graph format, making it ea...¹.
  • Third-Party Tools: Consider using tools specifically designed for creating ER diagrams. These tools allow you to visualize your schema, relationships, and dependencies effectively. One such tool is Software Ideas Modeler, which supports lookup tables and relationships².
  • Manual Approach: Draw your ER diagram manually based on the relationships you’ve defined in Unity Catalog. Represent tables as rectangles, primary keys as underlined attributes, and foreign keys as connecting lines.