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# dagster-cloud
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Henri Blancke

08/04/2023, 1:40 PM
👋 dagster team! Auto-materialization question... We have a lot of assets that depend on multiple upstream assets. We often see strange behavior when upstream assets update close to each other. For example: asset C depends on A and B. When A updates, the automaterializer kicks of a run for C but while it does that (or shortly before) B gets materialized. The materialization history for C shows asset B as "Will Update", and kicks off a run. When asset C and B eventually materialize, C is out of date again but C doesn't re-materialize to include changes from B, leading to missing data in C. Asset C detects it has upstream changes but no run is kicked off by the auto-materializer. Anything we can do to remedy this odd behavior? Thanks for the help 🙏
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rex

08/04/2023, 2:07 PM
@owen Could you take a look at this question when you get online?
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Henri Blancke

08/04/2023, 2:29 PM
It looks like each asset (C & B) is included in a different concurrent dbt run. They are updating at the same time essentially but in a different dbt run, making it so dbt can't determine to correct execution order. The first concurrent run seems to only include assets that depend on a frequently updated observable source?
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owen

08/04/2023, 7:35 PM
Hi @Henri Blancke! I'm looking into this, and it's definitely odd behavior. I believe you're correct that the fact that it's separating out the dbt executions into separate pieces is at play here, and I'm currently investigating why that might be happening
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Henri Blancke

08/04/2023, 7:36 PM
Thanks!
Appreciate the help 🙂 yay
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owen

08/04/2023, 10:21 PM
Alright, I believe this is related to: https://github.com/dagster-io/dagster/issues/13437, which we initially attempted a fix for, but ended up being unreliable, and so was reverted. In your graph, do you have any cases where you have a single call to load_assets_from..., which contains some dbt models which are upstream of some non-dbt asset, and other models which are downstream of that asset?
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Henri Blancke

08/07/2023, 1:29 PM
@owen yes in this particular case we have a dbt asset that's upstream from 2 non-dbt assets.