Need advise on best way to display/link tables in cascade/multilevel form/view

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Hello,

I appreciate if anyone can provide advise on how to achieve bellow requirement.
I have the following scenario:
-Project table
--Activities table
---Subactivities table
---- Tasks table
-----Actions table

Each project can have multiple activities, each activity can have multiple sub activities , each sub activity can have multiple tasks and each task can have multiple actions.

Thanks
Alex