[Core] Order of precedence for project flags, environment variables, and CLI flags

[dbeatty10]

Link to the page(s) on docs.getdbt.com requiring updates

These pages are all related:

• https://docs.getdbt.com/reference/global-configs/project-flags
• https://docs.getdbt.com/reference/global-configs/environment-variable-configs
• https://docs.getdbt.com/reference/global-configs/command-line-options

Tell us more about this update

It would be great if:

1. All three of these pages cross-link to each other
2. There were a common snippet across all three of these pages that explains the precedence order

The snippet could be similar / same as here.

Or it could be something as simple as this:

Config precedence

dbt will pick the config in the following order (lower takes priority):

1. project flags
2. environment variable
3. CLI flag

i.e., if all three are provided, then the CLI flag takes precedence.

Reviewers/Stakeholders/SMEs

Me :sunglasse

Related GitHub issues

Came up most recently here:

• https://github.com/dbt-labs/dbt-core/pull/9081#issuecomment-2144183788
• https://github.com/dbt-labs/dbt-core/pull/9081#issuecomment-2145329904

Additional information

Related to these issues:

• https://github.com/dbt-labs/docs.getdbt.com/issues/4362
• https://github.com/dbt-labs/docs.getdbt.com/issues/2894