delete_all.rb

# Deleting a large amount of records by invoking `destroy` on
# each record results in a single query per record.
deadbeat_users = User.where(payment_status: "deadbeat")
deadbeat_users.each do |deadbeat|
  deadbeat.destroy
end
# DELETE FROM users WHERE id = 13;
# DELETE FROM users WHERE id = 42;
# DELETE FROM users WHERE id = 49;
# DELETE FROM users WHERE id = 420;
# DELETE FROM users WHERE id = 666;
# ...

# Use `delete_all` to batch delete these records with one query, 
# if we do not need `after_destroy` callbacks to be invoked.  Note
# AR callbacks are pretty much an antipattern these days.
deadbeat_users.delete_all
# DELETE FROM users WHERE users.status = 'deadbeat';