Unit testing dbt models - Mini Project: Build & Apply

Unit Testing dbt Models

📖 Scenario: You work as a data analyst who builds data transformation models using dbt. To ensure your models are correct and reliable, you want to write unit tests that check your data logic before deploying to production.

🎯 Goal: Build a simple dbt model and write a unit test to verify that the model produces the expected results.

📋 What You'll Learn

Create a dbt model SQL file with a simple SELECT statement

Create a YAML test configuration file for the model

Write a dbt test that checks for expected data values

Run the test and display the test result

💡 Why This Matters

🌍 Real World

Data analysts and engineers use dbt to build reliable data pipelines. Unit testing models helps catch errors early and ensures data quality.

💼 Career

Knowing how to write and run dbt tests is a key skill for data engineers and analytics engineers working with modern data stacks.

1

Create a simple dbt model

Create a dbt model SQL file named models/simple_model.sql with the exact query: select 1 as id, 'test' as name

dbt

-- Create the file models/simple_model.sql with the query
-- Your code here

Need a hint?

This model returns a single row with id 1 and name 'test'.

2

Add a YAML test configuration

Create a YAML file named models/simple_model.yml with a test that checks the id column is unique in the simple_model model. Use the exact syntax: tests: - unique

dbt

# Create models/simple_model.yml with a unique test on id
# Your code here

Need a hint?

The YAML file defines tests for the model columns. Here we test that 'id' is unique.

3

Run the dbt test command

Run the command dbt test --select simple_model in your terminal to execute the unit test on the simple_model model.

dbt

# Run dbt test --select simple_model in terminal
# Your code here

Need a hint?

This command runs the tests defined for the simple_model only.

4

Display the test result

Print the expected output line PASS 1 test, 0 failures to show the test passed successfully.

dbt

# Print the test result below
# Your code here

Need a hint?

This output means your unit test passed with no errors.