title | id | sidebar_label | description |
---|---|---|---|
Model access |
model-access |
Model access |
Define model access with group capabilities |
:::info "Model access" is not "User access"
Model groups and access and user groups and access mean two different things. "User groups and access" is a specific term used in dbt Cloud to manage permissions. Refer to User access for more info.
The two concepts will be closely related, as we develop multi-project collaboration workflows this year:
- Users with access to develop in a dbt project can view and modify all models in that project, including private models.
- Users in the same dbt Cloud account without access to develop in a project cannot view that project's private models, and they can take a dependency on its public models only. :::
Models can be grouped under a common designation with a shared owner. For example, you could group together all models owned by a particular team, or related to modeling a specific data source (github
).
Why define model groups
? There are two reasons:
- It turns implicit relationships into an explicit grouping, with a defined owner. By thinking about the interface boundaries between groups, you can have a cleaner (less entangled) DAG. In the future, those interface boundaries could be appropriate as the interfaces between separate projects.
- It enables you to designate certain models as having "private" access—for use exclusively within that group. Other models will be restricted from referencing (taking a dependency on) those models. In the future, they won't be visible to other teams taking a dependency on your project—only "public" models will be.
If you follow our best practices for structuring a dbt project, you're probably already using subdirectories to organize your dbt project. It's easy to apply a group
label to an entire subdirectory at once:
models:
my_project_name:
marts:
customers:
+group: customer_success
finance:
+group: finance
Each model can only belong to one group
, and groups cannot be nested. If you set a different group
in that model's YAML or in-file config, it will override the group
applied at the project level.
Some models are implementation details, meant for reference only within their group of related models. Other models should be accessible through the ref function across groups and projects. Models can set an access modifier to indicate their intended level of accessibility.
Access | Referenceable by |
---|---|
private | Same group |
protected | Same project (or installed as a package) |
public | Any group, package, or project. When defined, rerun a production job to apply the change |
If you try to reference a model outside of its supported access, you will see an error:
dbt run -s marketing_model
...
dbt.exceptions.DbtReferenceError: Parsing Error
Node model.jaffle_shop.marketing_model attempted to reference node model.jaffle_shop.finance_model,
which is not allowed because the referenced node is private to the finance group.
By default, all models are protected
. This means that other models in the same project can reference them, regardless of their group. This is largely for backward compatibility when assigning groups to an existing set of models, as there may already be existing references across group assignments.
However, it is recommended to set the access modifier of a new model to private
to prevent other project resources from taking dependencies on models not intentionally designed for sharing across groups.
# First, define the group and owner
groups:
- name: customer_success
owner:
name: Customer Success Team
email: [email protected]
# Then, add 'group' + 'access' modifier to specific models
models:
# This is a public model -- it's a stable & mature interface for other teams/projects
- name: dim_customers
group: customer_success
access: public
# This is a private model -- it's an intermediate transformation intended for use in this context *only*
- name: int_customer_history_rollup
group: customer_success
access: private
# This is a protected model -- it might be useful elsewhere in *this* project,
# but it shouldn't be exposed elsewhere
- name: stg_customer__survey_results
group: customer_success
access: protected
Models with materialized
set to ephemeral
cannot have the access property set to public.
For example, if you have a model config set as:
{{ config(materialized='ephemeral') }}
And the model access is defined:
models:
- name: my_model
access: public
It will lead to the following error:
❯ dbt parse
02:19:30 Encountered an error:
Parsing Error
Node model.jaffle_shop.my_model with 'ephemeral' materialization has an invalid value (public) for the access field
These are different!
Specifying access: public
on a model does not trigger dbt to automagically grant select
on that model to every user or role in your data platform when you materialize it. You have complete control over managing database permissions on every model/schema, as makes sense to you & your organization.
Of course, dbt can facilitate this by means of the grants
config, and other flexible mechanisms. For example:
- Grant access to downstream queriers on public models
- Restrict access to private models, by revoking default/future grants, or by landing them in a different schema
As we continue to develop multi-project collaboration, access: public
will mean that other teams are allowed to start taking a dependency on that model. This assumes that they've requested, and you've granted them access, to select from the underlying dataset.
You can ref
a model from another project in two ways:
- Project dependency: In dbt Cloud Enterprise, you can use project dependencies to
ref
a model. dbt Cloud uses a behind-the-scenes metadata service to resolve the reference, enabling efficient collaboration across teams and at scale. - "Package" dependency: Another way to
ref
a model from another project is to treat the other project as a package dependency. This requires installing the other project as a package, including its full source code, as well as its upstream dependencies.
Source code installed from a package becomes part of your runtime environment. You can call macros and run models as if they were macros and models that you had defined in your own project.
For this reason, model access restrictions are "off" by default for models defined in packages. You can reference models from that package regardless of their access
modifier.
The project is installed as a package can optionally restrict external ref
access to just its public models. The package maintainer does this by setting a restrict-access
config to True
in dbt_project.yml
.
By default, the value of this config is False
. This means that:
- Models in the package with
access: protected
may be referenced by models in the root project, as if they were defined in the same project - Models in the package with
access: private
may be referenced by models in the root project, so long as they also have the samegroup
config
When restrict-access: True
:
- Any
ref
from outside the package to a protected or private model in that package will fail. - Only models with
access: public
can be referenced outside the package.
restrict-access: True # default is False