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MySQL按分组日期范围排序

[英]MySQL ordering by grouped date ranges

I have a model with the following four scopes: 我有一个具有以下四个范围的模型:

scope :active, -> { where("start_at <= '#{Time.now.utc}' AND end_at > '#{Time.now.utc}'") }
scope :ended, -> { where("end_at < '#{Time.now.utc}'") }
scope :coming_soon, -> { where("start_at > '#{Time.now.utc}' AND start_at < '#{Time.now.utc+6.hours}'") }

I want to be able to do something like (pseudocode, just trying to give an idea): 我希望能够做类似的事情(伪代码,只是试图给出一个想法):

Model.all.order(active, coming_soon, ended)

The result would be all rows from that table, sorted by rows meeting the active constraints first, followed by the ones meeting the coming_soon constraint, and finally all the ones meeting the ended constraints. 结果将是该表中的所有行, coming_soon先满足active约束的行排序,然后再满足coming_soon约束的行排序,最后再满足ended约束的所有行排序。

I added the following scope and it seems to have solved my problem: 我添加了以下范围,它似乎已经解决了我的问题:

scope :time_sorted, -> { 
    select("events.*, CASE 
      WHEN start_at <= '#{Time.now.utc}' AND end_at > '#{Time.now.utc}' THEN 1
      WHEN end_at < '#{Time.now.utc}' THEN 2
      WHEN start_at > '#{Time.now.utc}' AND start_at < '#{Time.now.utc+6.hours}' THEN 3 ELSE 4
      END AS formula")
    .order("formula ASC")
}

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