Asset Selection Syntax#

To specify an asset selection as a string, Dagster supports a simple query syntax. This selection syntax is accepted in a few different places:

• The list and materialize commands in the asset command-line interface.
• The asset filter text box on the asset graph page, in the UI.
• The selection parameter of define_asset_job. (This parameter alternatively accepts an AssetSelection object, which supports more complex selections built from compositions of Python objects.)

It works as follows:

• A query includes a list of clauses. Clauses are separated by commas, except in the case of the selection parameter of define_asset_job, where each clause is a separate element in a list.
• A clause can be an asset key, in which case that asset is selected.
• An asset key with multiple components can be specified by inserting slashes between the components.
• A clause can be an asset key preceded by *, in which case that asset and all of its ancestors (upstream dependencies) are selected.
• A clause can be an asset key followed by *, in which case that asset and all of its descendents (downstream dependencies) are selected.
• A clause can be an asset key followed by any number of +s, in which case that asset and descendents up to that many hops away are selected.
• A clause can be an asset key preceded by any number of +s, in which case that asset and ancestors up to that many hops away are selected.

Clause examples

• some_asset: select "some_asset" itself
• my/prefixed/asset: select the asset whose AssetKey in Python is AssetKey(["my", "prefixed", "asset"])
• *some_asset: select "some_asset" and all ancestors (upstream dependencies).
• some_asset*: select "some_asset" and all descendants (downstream dependencies).
• *some_asset*: select "some_asset" and all of its ancestors and descendants.
• +some_asset: select "some_asset" and its direct parents.
• some_asset+++: select "some_asset" and its children, its children's children, and its children's children's children.