PR review workflows for dbt changes - Step-by-Step Execution

Concept Flow - PR review workflows for dbt changes

Developer makes dbt changes

↓

Create Pull Request (PR)

↓

Automated CI runs dbt tests & builds

↓

Tests pass

↓

Reviewers check

↓

Approve PR

↓

Merge PR

↓

Deploy changes

↓

Monitor & validate

This flow shows how dbt changes go from development, through automated tests and reviews, to deployment.

Execution Sample

dbt

git checkout -b feature/dbt-model
# Make changes to models
git add .
git commit -m "Add new dbt model"
git push origin feature/dbt-model
# Create PR in GitHub
# CI runs: dbt run, dbt test
# Reviewers approve
# Merge PR

This code simulates the steps a developer takes to create a PR with dbt changes and how CI and reviews happen.

Execution Table

Step	Action	Result	Next Step
1	Developer creates feature branch and edits dbt models	Local changes ready	Push branch to remote
2	Push branch to remote repository	Branch available on remote	Create Pull Request (PR)
3	Create PR in GitHub	PR opened, triggers CI	CI runs dbt commands
4	CI runs 'dbt run' and 'dbt test'	Tests pass	Reviewers notified
5	Reviewers check code and tests	Approve PR	Merge PR
6	Merge PR into main branch	Changes merged	Deploy changes
7	Deploy changes to production	New dbt models live	Monitor and validate
8	If tests fail at step 4	CI fails, PR blocked	Developer fixes errors and pushes updates
9	If reviewers request changes at step 5	PR not approved	Developer updates PR
10	After fixes, repeat CI and review	Tests pass and approved	Merge PR

💡 Process ends when PR is merged and changes deployed successfully.

Variable Tracker

Variable	Start	After Step 2	After Step 4	After Step 5	Final
branch_status	local changes	pushed to remote	unchanged	unchanged	merged
ci_status	not started	triggered	tests pass/fail	tests pass	completed
pr_status	not created	open	open	approved	merged
deployment_status	not deployed	not deployed	not deployed	not deployed	deployed

Key Moments - 3 Insights

Why does the PR not merge if CI tests fail?

Because the execution_table row 8 shows that if tests fail, the PR is blocked to prevent broken code from merging.

What happens if reviewers request changes after CI passes?

Row 9 explains that the PR is not approved and the developer must update the PR before merging.

Why do we need to push the branch before creating a PR?

Row 2 shows the branch must be on the remote repository so the PR can be created and CI triggered.

Visual Quiz - 3 Questions

Look at the execution_table, what is the status of the PR after step 3?

A PR is merged

B PR is open and CI is triggered

C PR is closed

D PR is approved

💡 Hint

Check row 3 in the execution_table for PR status after creation.

At which step does the deployment happen according to the execution_table?

A Step 7

B Step 4

C Step 6

D Step 5

💡 Hint

Look for the step mentioning 'Deploy changes to production' in the execution_table.

If tests fail during CI, what is the next action?

A Merge PR anyway

B Reviewers approve PR

C Developer fixes errors and pushes updates

D Deployment starts

💡 Hint

Refer to row 8 in the execution_table describing CI failure.

Concept Snapshot

PR Review Workflow for dbt Changes:
1. Developer creates feature branch and edits dbt models.
2. Push branch and create PR to trigger CI.
3. CI runs dbt commands (run, test).
4. Reviewers approve if tests pass.
5. Merge PR and deploy changes.
6. Fix errors if tests fail or reviewers request changes.

Full Transcript

This visual execution shows the typical PR review workflow for dbt changes. A developer first creates a feature branch and edits dbt models locally. Then they push the branch to the remote repository and create a Pull Request (PR). This PR triggers Continuous Integration (CI) which runs dbt commands like 'dbt run' and 'dbt test'. If the tests pass, reviewers check the code and approve the PR. Once approved, the PR is merged into the main branch and changes are deployed to production. If tests fail or reviewers request changes, the developer must fix the issues and update the PR. This cycle repeats until the PR passes all checks and is merged successfully. The variable tracker shows the state of branch, CI, PR, and deployment statuses at key steps. The key moments clarify common confusions about why PRs might be blocked or require updates. The quiz questions help reinforce understanding by referencing specific steps in the workflow.

Practice

1. What is the main purpose of using a PR (Pull Request) review workflow in dbt projects?

easy

A. To ensure changes are reviewed and tested before merging

B. To speed up merging without checks

C. To delete old branches automatically

D. To create new dbt models without review

Solution

1. Step 1: Understand PR review workflow purpose

   PR review workflows are designed to check code changes carefully before they become part of the main project.

2. Step 2: Identify the correct purpose in dbt context

   In dbt, this means reviewing and testing data models to avoid errors and keep the project reliable.

3. Final Answer:

   To ensure changes are reviewed and tested before merging -> Option A

4. Quick Check:

   PR review = review and test before merge [OK]

Hint: PR reviews catch errors before merging [OK]

Common Mistakes:

• Thinking PRs speed up merging without checks
• Confusing PR reviews with branch deletion
• Assuming PRs create models automatically

2. Which of the following is the correct syntax to create a new branch for a dbt PR workflow using Git?

easy

A. git branch new-feature

B. git merge new-feature

C. git push new-feature

D. git checkout -b new-feature

Solution

1. Step 1: Understand Git branch creation commands

   To create and switch to a new branch in one step, use git checkout -b branch-name.

2. Step 2: Identify the correct command for new branch creation

   git checkout -b new-feature uses git checkout -b new-feature, which creates and switches to the branch.

3. Final Answer:

   git checkout -b new-feature -> Option D

4. Quick Check:

   New branch creation = git checkout -b [OK]

Hint: Use git checkout -b to create and switch branch [OK]

Common Mistakes:

• Using git branch without switching
• Confusing merge with branch creation
• Trying to push before creating branch

3. Given this simplified dbt test command in a PR workflow:

dbt test --models my_model

What will happen if the model my_model has a failing test?

medium

A. The command deletes the model automatically

B. The command completes successfully with no error

C. The command fails and returns a non-zero exit code

D. The command ignores the test and continues

Solution

1. Step 1: Understand dbt test behavior

   When a dbt test fails, the command returns a non-zero exit code indicating failure.

2. Step 2: Identify the effect of a failing test in PR workflow

   This failure stops the PR from merging until the issue is fixed.

3. Final Answer:

   The command fails and returns a non-zero exit code -> Option C

4. Quick Check:

   Failing test = command fails with error code [OK]

Hint: Failing dbt tests cause command to fail [OK]

Common Mistakes:

• Assuming tests pass silently
• Thinking dbt deletes models on failure
• Believing tests are ignored automatically

4. You wrote a dbt model and created a PR, but the automated tests fail. Which of the following is the best way to debug the issue?

medium

A. Ignore the test failures and merge the PR

B. Check the test logs and fix the model SQL accordingly

C. Delete the model file and close the PR

D. Merge the PR and fix errors later in production

Solution

1. Step 1: Understand the role of test logs in debugging

   Test logs show which tests failed and why, helping identify SQL errors or data issues.

2. Step 2: Choose the correct debugging approach

   Fixing the model SQL based on logs ensures the PR passes tests before merging.

3. Final Answer:

   Check the test logs and fix the model SQL accordingly -> Option B

4. Quick Check:

   Debug by reviewing logs and fixing code [OK]

Hint: Use test logs to find and fix errors [OK]

Common Mistakes:

• Ignoring test failures
• Deleting models unnecessarily
• Merging broken code into main branch

5. In a team using dbt with PR review workflows, which combination of practices best ensures data model quality before merging?

hard

A. Create feature branches, run automated tests, and require team approval

B. Directly commit to main branch and run tests after merging

C. Skip tests and rely on manual checks only

D. Merge PRs without reviews to speed up deployment

Solution

1. Step 1: Identify best practices in PR workflows

   Using feature branches isolates changes, automated tests catch errors early, and team approval ensures quality review.

2. Step 2: Compare options to find the best combination

   Create feature branches, run automated tests, and require team approval includes all these practices, while others skip important steps or risk errors.

3. Final Answer:

   Create feature branches, run automated tests, and require team approval -> Option A

4. Quick Check:

   Branch + tests + review = quality assurance [OK]

Hint: Combine branches, tests, and reviews for quality [OK]

Common Mistakes:

• Committing directly to main branch
• Skipping automated tests
• Merging without team review