Okay, so always on teacher, 1 or more Learners.

Are subjects a set thing? That is, only a limited amount of subjects (expanded at will), or can it be anything, that is, just a quick note.

I don't believe you need a session id. As one person can only teach one session at a time, the natural key is Teacher/Time. And for Person, shouldn't it be employee? And, do Employees already have unique id, such as their company email address?

In reply to Re^7: Avoiding SQL double jeopardy by Pope-O-Matik
in thread Avoiding SQL double jeopardy by GrandFather

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