It seems i've found a bug. When you press "materialize" on an asset group that both contains partitioned and non partitioned assets, it seems that it materializes the non-partitioned asset in each of the backfills created, meaning the same asset will go through the same materialization for no particular reason.

I noted the same behaviour as well

right. the end result is the same; it is probably (for everyone) unintended behaviour. least a warning could be written.

When I spoke to the Dagster team, they said that, at present, in situations like this, we need to backfill the partitioned asset on its own, then run it as part of a group. Not ideal, but they are aware of the limitation.

I ended up splitting it into two different asset groups for ease.

Thanks for raising this! This is actually something that will be fixed in the next couple of releases. In the future, backfills will be smarter i.e. for the situation you mentioned only one materialization of a non-partitioned asset will be generated

This appears to be included in the latest release https://dagster.slack.com/archives/C01UC74PQAF/p1672972988388149

Woo thanks 🙏