Explain behavior of config.get

[dbeatty10]

Contributions

• I have read the contribution docs, and understand what's expected of me.

Link to the page on docs.getdbt.com requiring updates

Docs to update:

• https://docs.getdbt.com/reference/dbt-jinja-functions/config#configget
• https://docs.getdbt.com/reference/resource-configs/where#custom-logic

#3689 was merged, which might already address the 2nd bullet point.

What part(s) of the page would you like to see updated?

See here for background and details:

• [CT-2802] [Feature] For built-in node configs: if not defined, do not add None value to config dbt-core#8047 (comment)

Additional information

In an internal slack thread, @gshank noted that:

Instead of config.get("some_name", "some_default") it works with built-in configs to do config.get("some_name") or "some_default" instead

So if I'm interpreting that correctly, then we'd recommend doing this to get behavior that is similar to coalesce():

{% set where = config.get("where") or "your_desired_default_goes_here" %}

History

Here's some historical issues related to how we've reach the current implementation:

• [CT-2802] [Feature] For built-in node configs: if not defined, do not add None value to config dbt-core#8047
• [CT-2122] [Bug] project variables are None if dbt.config.get is called within string interpolation dbt-core#6976
• [CT-1545] [Bug] dbt.config.get returns Undefined instead of the default value in Python model dbt-core#6309
• [Bug] config.get(config.field, default_value) not working properly? dbt-core#4273
• Calling config.get() within a config() function. dbt-core#2101