Yes, teacher ID could be used as the session (pair) ID.

Available topics are expected to be quite dynamic. Someone could change the topic they offer each week, or stick to the same topic for long periods of time, or have several topics on offer at the same time.

Person / Employee is not an interesting distinction. This system is unrelated to any "business" database. In fact it's quite likely that visitors will take part in sessions.

Email addresses are stored in the People database as an ID, but can be changed. The autoincremented internal ID is the "authoritative" identifier in the system.

Perl is the programming world's equivalent of English

In reply to Re^8: Avoiding SQL double jeopardy by GrandFather
in thread Avoiding SQL double jeopardy by GrandFather

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