Chaining scopes with OR

[rida-elbahtouri]

Description

when we have scopes like this

  def unassigned
      where(assigned_at: Time.zone.now..12.hours.ago).or(assigned_at: nil)
   end

Only the query before or will be applied to existing data, and the query after OR seems to be applied on all records, in the above case it will be the equivalent of this:

 existing_query.where(assigned_at: Time.zone.now..12.hours.ago) + Case.where(assigned_at: nil) 
   

I updated that to this:

  def unassigned
      case_ids = where(assigned_at: Time.zone.now..12.hours.ago).or(assigned_at: nil).select_map(:id)
      where(id: case_ids)
   end

this fixed the issue, but I am wondering if there is a better way to handle this.

[janko]

The #or here will be applied at level of the whole dataset, it won't regard the last #where filter. What you want is build an OR expression that you pass to #where:

where(Sequel[assigned_at: Time.zone.now..12.hours.ago] | Sequel[assigned_at: nil])

See https://sequel.jeremyevans.net/rdoc/files/doc/sql_rdoc.html#label-Boolean+Operators+-28AND+OR-29.

[rida-elbahtouri]

Perfect that's what I was looking for, thank you so much @janko.