database normalization first normal form confusion - when should separating tables out -


please consider academic view not practical engineering view. 1nf , 1nf only.

considering unnormalized form below, primary key {trainingdatetime, employeenumber}, how make first normal form?

if separate course, instructor , employee tables out separate tables, automatically become 3nf.

unf!

if split different rows, like:

enter image description here

but problem here obvious - primary key no longer valid.

changing primary key {trainingdatetime, employeenumber, employeeskill} doesn't seems sensible solution.

just make satisfy 1nf, need have seperate rows individual teaching skills. should ensuring higher normal forms satisfied splitting tables. 1 row should have teaching skill advanced php , second row advanced java , third row advanced sql , on same employee.


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