Help for ERC - employee overtime hourly rate

[spylo]

Hi,
I have to design a database to keep track of the Overtime HourlyRate for employees.

Hourly rate depends on the type of overtime (day, night, holiday day, holiday night) - sorry I don't know the correct english definition for that- and the salary grade.

For example the HolidayNight overtime for the A1 grade has a hourly rate of 10€, but the same type of overtime for the B2 grade has an hourly rate of 8€.

I came up with this solution (not considering Employee for now):
01_TariffeOrarie.1.png

A further step is to consider that HourlyRate may change but we cannot have two hourlyrate with the same stard date for the same overtime type and salary grade.
This is what I thought

01_TariffeOrarie.2.png

Is that correct?