This levvr intstruction video handles the basics of determining the direction of a relation and how this changes deletion behaviour.
Video content
0:00 Introduction
0:40 Rule 1 - Ownership
3:20 Rule 2 - Timeline
4:50 Rule 3 - Block deletion
6:24 Rule 4 - Constrained cardinality
7:30 Deletion behaviour
8:55 Copy behaviour
9:40 Information snippets
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