I am also confused a bit by asset materialization in SDAs in dagster. I had expected that if a downstream asset needs materialization, that since dagster knows what the dependencies are, it will materialize all the upstream assets for me first. But i think my mental model (which comes from Makefiles) is again wrong. It seems i must explicitly materialize all, or in the context of a job as in the screenshot below, add all the dependencies in the

selection

argument...

You should be able to drill down to a subset of your assets using the search bar in the top left;

my_asset_key+

will give you all downstream assets for example, and then clicking materialize will only materialize that set of assets

Sure but my iomanager definition in terms of asset key ‘source_’ hurts this. It won’t read a already materialized upstream asset cause it again thinks it should hit the upstream asset path in the iomanager and there is no ‘source_’ to indicate not to. As I said, need something robust like “this is the root level asset” being materialized to do this properly!