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Chohang Ng

06/03/2021, 1:57 AM
I am confused how the upstream_tasks work. Here I want to execute them in this order (2>(1,3)>4>5). Does this look right? For some reasons, only flow 1,2 got executed
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Chris White

06/03/2021, 2:11 AM
Hi @Chohang Ng - for debugging dependencies I highly recommend using
flow.visualize()
so you can see your task graph. In this case, you are creating 2 copies of Flow 1:
flow_1_flow().set_upstream(flow_2_flow()) # <--- here
step_2 = flow_4_flow(upstream_tasks = [flow_1_flow(),flow_3]) # <--- and here
I can’t explain why you’re only seeing flow 1 and 2 though, you should still see all 5 flows execute based on the code you’e provided here
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Chohang Ng

06/03/2021, 3:18 PM
I wondered why I needed to call flow_1_flow(). In this example, https://docs.prefect.io/core/idioms/flow-to-flow.html It seems like I can just refer to the flow_1_flow variable instead of doing flow_1_flow()