It sounds like you are describing data that would normally kept in a 7 column spreadsheet.
AI2 has a spreadsheet component:
To keep that data in TinyDB you would need to worry about how much data you would accumulate over time.
The simplest way is to start with a fixed tag 'MyAppData' for example, initially an empty list. Add a row (list) for every new 7 item addition. That's a list of lists (a table).
After adding every row, save the table back into TinyDB under that same tag.
Before adding new data, get a fresh copy of the table from TinyDB, then immediately save the entire table back into TinyDB.
There are advanced list blocks you can use to filter the table by year and month.