Built-in Jinja context variables in dbt - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of Jinja variable usage in dbt model

What is the output of this Jinja snippet in a dbt model if the model name is sales_summary?

dbt

{% set model_name = this.name %}
{{ model_name }}

A None

B this.name

C {{ this.name }}

D sales_summary

💡 Hint

The this variable refers to the current model's context.

The this.name returns the name of the current model as a string, so the output is 'sales_summary'.

❓ data_output

intermediate

Using var to pass variables in dbt

Given the dbt model code below, what will be the output of {{ var('region', 'all') }} if no variable region is passed during runtime?

dbt

{{ var('region', 'all') }}

A all

B region

C None

D Error: variable not found

💡 Hint

The var function returns the default value if the variable is not set.

Since no variable named 'region' is passed, the default value 'all' is returned.

🧠 Conceptual

advanced

Purpose of config in dbt Jinja context

Which of the following best describes the purpose of the config variable in dbt's Jinja context?

A It contains the database connection credentials.

B It stores the runtime environment variables for the dbt project.

C It allows setting model-specific configurations like materialization and tags.

D It holds the compiled SQL code of the model.

💡 Hint

Think about how you customize model behavior in dbt.

The config variable is used to set configurations such as materialization type, file paths, and tags for the current model.

🔧 Debug

advanced

Error caused by misuse of this in dbt model

What error will occur if you try to access this.database in a dbt model when the database is not defined in the profile?

dbt

{{ this.database }}

A None (outputs empty string)

B UndefinedError: 'database' is not defined on 'this'

C RuntimeError: Database connection failed

D KeyError: 'database'

💡 Hint

Check what happens when a property is missing in Jinja context.

If the database is not set, accessing this.database raises an UndefinedError because the attribute does not exist.

🚀 Application

expert

Using run_started_at for incremental models

You want to filter rows in an incremental dbt model to only include data updated after the current run started. Which Jinja variable should you use in your SQL WHERE clause?

A run_started_at

B this.schema

C target.name

D invocation_id

💡 Hint

This variable holds the timestamp when the dbt run began.

The run_started_at variable contains the timestamp of when the dbt run started, useful for filtering incremental data.