It’s not possible to have multiple start / end dates for a specific data type. Instead you need to think about how to utilise the current system possibilities to best meet your needs for a data structure.
So, in your example of a Math Class ask yourself some questions.
- How many classes
- Do classes span multiple years
- How do people relate to the class
- Do people switch class mid year
Etc.
Assuming a math class lasts one year I would create a class data type with a naming convention of something like MathClass1-2020, MathClass2-2020, MatchClass1-2021 etc Each class would then have a start and end date for that given year. You can then associate people(students) with a specific class/year.
With regards the band example (which is something I actually use) I have three data types:
- Band
- Lineup
- Musician
Each data type has its own start/end date i.e. When band formed/disbanded, when lineup existed, musicians birth/death. I relate the musician to the lineup and the lineup to the band. This gives me something like this…
I don’t think this is the only approach. It very much depends on how you want to visualise the data as well as maintaining it.
Hope this helps.
