Finding number of projects that are levels

gistfile1.rb

def query_for_terms(terms)
  query = ""
  terms.each do |term|
    query += "lower(substring(title from 0 for 30)) LIKE '%#{term}%' OR "
  end
  query.chomp("OR ")
end

def projects_arel(weeks_ago)
  start_date = Time.now.beginning_of_week - 1.day - weeks_ago.weeks
  end_date =  start_date + 7.days
  Project.where("updated_at > ? AND updated_at < ? AND PUBLISHED IS TRUE", start_date, end_date)
end

query = query_for_terms(["level", "done"])
10.times.each do |time|
  puts "#{time} weeks ago"
  projects_count = projects_arel(time).count
  levels_count = projects_arel(time).where(query).count
  puts "projects count: #{projects_count} levels count: #{levels_count}"
  puts "----------------------"
end