Test severity levels in dbt - Mini Project: Build & Apply

Test Severity Levels in dbt

📖 Scenario: You are working on a data project using dbt. You want to ensure your data quality by adding tests with different severity levels. This helps you decide which test failures should stop your workflow and which should just warn you.

🎯 Goal: Learn how to add tests in dbt with different severity levels: error and warn. You will create a simple model, add tests, and configure their severity.

📋 What You'll Learn

Create a dbt model with sample data

Add a test with severity level error

Add a test with severity level warn

Run dbt tests and observe output

💡 Why This Matters

🌍 Real World

Data teams use dbt tests with severity levels to catch critical data issues early and allow less critical warnings to be reviewed later.

💼 Career

Understanding test severity in dbt helps data analysts and engineers maintain data quality and reliability in production pipelines.

1

Create a simple dbt model

Create a dbt model file named models/customers.sql with the following SQL code:
select 1 as id, 'Alice' as name union all select 2, 'Bob'

dbt

# Create the file models/customers.sql with the SQL query
# Your code here

Need a hint?

Make sure the file is named exactly customers.sql inside the models folder and contains the exact SQL query.

2

Add a test with severity level error

In the tests folder, create a test file named not_null_id.yml with this content:
version: 2
models:
- name: customers
tests:
- not_null:
column_name: id
severity: error

dbt

select 1 as id, 'Alice' as name union all select 2, 'Bob'
# Create the file tests/not_null_id.yml with the specified test and severity
# Your code here

Need a hint?

The test file must be YAML format with version 2 and specify severity: error for the not_null test on id column.

3

Add a test with severity level warn

Add another test in the same tests/not_null_id.yml file for the name column with severity set to warn. The YAML should look like this:
version: 2
models:
- name: customers
tests:
- not_null:
column_name: id
severity: error
- not_null:
column_name: name
severity: warn

dbt

select 1 as id, 'Alice' as name union all select 2, 'Bob'

# tests/not_null_id.yml content:
# version: 2
# models:
# - name: customers
#   tests:
#     - not_null:
#         column_name: id
#         severity: error
# Add a not_null test for column name with severity warn
# Your code here

Need a hint?

Add the second not_null test for the name column with severity set to warn under the same model.

4

Run dbt tests and observe severity output

Run dbt test in your terminal to execute the tests. Observe that if the id column test fails, dbt stops with an error. If the name column test fails, dbt shows a warning but continues.

dbt

select 1 as id, 'Alice' as name union all select 2, 'Bob'

# tests/not_null_id.yml content:
# version: 2
# models:
# - name: customers
#   tests:
#     - not_null:
#         column_name: id
#         severity: error
#     - not_null:
#         column_name: name
#         severity: warn
# Run dbt test and observe output
# Your code here

Need a hint?

Use the terminal to run 'dbt test' and watch the output for error and warning messages.