search for users age based on date of birth

Question

I am having trouble understanding how to perform a range search of a users age based on their date of birth. My DB stores the user dob only. I want for visitors to use the advanced search form and perform age searches such as '18-23', '28-36', etc.

I have tried a few things but none seem to work. I added scope to User model, def min & max age, and one other solution that did not pan out. Maybe I am getting some of the code right but not executing the other part. I am not sure. If someone can guide me the right direction that would be great so I can learn this.

When I perform a search based on selected age it returns all users.

Search Model:

attr_accessible :age, :children, :ethnicity, :career, :gender, :religion, :zip_code, :birthday, :max_age, :min_age, :youngest_age, :oldest_age

  def users
    @users ||= find_users
  end

    private

  def find_users
    users = User.order(:id)
    users = users.where(gender: gender) if gender.present?
       users = users.where(zip_code: zip_code) if zip_code.present?
       users = users.where(children: children) if children.present?
       users = users.where(religion: religion) if religion.present?
       users = users.where(ethnicity: ethnicity) if ethnicity.present?
       users = users.where("birthday >= ? AND birthday <= ?", 80.years.ago + 1.day, 18.years.ago)


       users
  end
end

Search_Form:

<%= select(@object, :youngest_age, (18..75).to_a) %> to <%= select(@object, :oldest_age, (18..75).to_a) %>

Answer 1

This should do it:

# view
<%= select @object, :min_age, (18..75).to_a %>
to
<%= select @object, :max_age, (18..75).to_a %>

# controller
def show
  @search = Search.find(params[:id])
  @users = @search.users
end

# Search model
def find_users
  users = User.order(:id)
  users = users.where(gender: gender) if gender.present?
  users = users.where(zip_code: zip_code) if zip_code.present?
  users = users.where(children: children) if children.present?
  users = users.where(religion: religion) if religion.present?
  users = users.where(ethnicity: ethnicity) if ethnicity.present?

  if min_age.present? && max_age.present?
    min = [ min_age, max_age ].min
    max = [ min_age, max_age ].max
    min_date = Date.today - min.years
    max_date = Date.today - max.years
    users = users.where("birthday BETWEEN ? AND ?", max_date, min_date)
  end
  users
end

Answer 2

You'll need to pass back two parameters from your search form to your controller. I'm assuming those will be params[:youngest_age] and params[:oldest_age] for this. I'm also assuming those will be integers (ex: params[:youngest_age] = 18)

youngest_age = params[:youngest_age].years
oldest_age = params[:oldest_age].years

User.where("birthday >= ? AND birthday <= ?", Date.today - youngest_age, Date.today - oldest_age)