Rails SQL查询两个日期之间的差异超过2周

Question

I have a table that has 2 columns "date_from" and "date_to". I have to make a query which should return results where "date_to" - "date_from" == "2 weeks".

Something like this:

User.where('date_to - date_from == 2.weeks').

Answer 1

Define this on user:

def self.two_weeks
   where(date_to: date_from + 2.weeks)
end

Then you can just call User.two_weeks

Can also be done as a scope, if you prefer:

scope :two_weeks, -> { where(date_to: date_from + 2.weeks) }

It's good to keep these kinds of things on the model anyway, so that you can change them in one place if they need to be tweaked

Answer 2

这应该工作，至少对于mysql

User.where('1 + DATEDIFF(date_to, date_from) >= 14')