discourse/db/fixtures/001_categories.rb

require 'migration/column_dropper'

# fix any bust caches post initial migration
ActiveRecord::Base.send(:subclasses).each { |m| m.reset_column_information }

SiteSetting.refresh!
uncat_id = SiteSetting.uncategorized_category_id
uncat_id = -1 unless Numeric === uncat_id

if uncat_id == -1 || !Category.exists?(uncat_id)
  puts "Seeding uncategorized category!"

  count = DB.exec "SELECT 1 FROM categories WHERE lower(name) = 'uncategorized'"
  name = 'Uncategorized'
  name << SecureRandom.hex if count > 0

  result = DB.query_single "INSERT INTO categories
          (name,color,slug,description,text_color, user_id, created_at, updated_at, position, name_lower)
   VALUES ('#{name}', '0088CC', 'uncategorized', '', 'FFFFFF', -1, now(), now(), 1, '#{name.downcase}' )
   RETURNING id
  "
  category_id = result.first.to_i

  DB.exec "DELETE FROM site_settings where name = 'uncategorized_category_id'"
  DB.exec "INSERT INTO site_settings(name, data_type, value, created_at, updated_at)
           VALUES ('uncategorized_category_id', 3, #{category_id}, now(), now())"
end