Date categorization

Question

I have a date in SQL (assuming 01/15/2021). I need to be able to categorize this date as past 30\past60\past365. What would be the best way to do it?
So my result set should show which category this date falls under. I can have 3 different columns that say past 30 or past 60 and say Y or N for this date. But I need one column that I can use for the categorization. This date will fall under past 30 and past 60 days.
How do I categorize it?

Answer 1

I think that you can use something like this:

select *,
    case
        when days <= 30 then 'past 30'
        when days <= 60 then 'past 60'
        when days <= 365 then 'past 365'
    end as Category
from MyTable
cross apply (values (datediff(day, MyDateColumn, GETDATE()))) t(days)