Fixed-in-time basic TODO aggregation

[mentaloid]

@Siferiax

Not something you can see in the schema apparently, but journal-day is a number in format yyyymmdd.
There is no date operations.
I believe @mentaloid had some complicated math elsewhere on the forum?

I’m linking the math for Datalog and Clojure respectively. But these are complicated mostly because of calculating the day of the week. For extracting the needed values out of the yyyymmdd format, quotient and modulo are enough.