Example of how to disable foreign keys for a particular context

without_foreign_keys.rb

RSpec.shared_context "without foreign key constraints", :disable_foreign_keys do
  def without_foreign_key_checks
    ActiveRecord::Base.connection.execute('SET foreign_key_checks = 0;')
    yield
  ensure
    ActiveRecord::Base.connection.execute('SET foreign_key_checks = 1;')
  end

  around(:example) { |ex| without_foreign_key_checks(&ex) }
end

# usage:
# RSpec.describe "Something", :disable_foreign_keys do
#   # ...
# end

To others using this: if you get uninitialized constant DB, try replacing DB.run with ActiveRecord::Base.connection.execute