Question

I have an app where users are approved by an admin after registering. I need a little help filtering out the admins in the members list.

This is my index method:

def index
  if params[:is_approved].to_i == 0
    @users = User.find_all_by_is_approved(0) #returns all unapproved users
  else
    @users = User.find_all_by_is_approved(1) #here I wanna filter out the admins
  end   
end

I tried to add && User.find_all_by_is_admin(0) but then I get all the users that are not admins, i.e., the unapproved users.

Admins are users but have a column is_admin set to true, and I dont want to display them.

Answer 1

If you want the list of users who are approved but aren’t admins:

User.where(:is_approved => 1, :is_admin => 0)

or if you want to write it in the style you were using you could do:

User.find_all_by_is_approved_and_is_admin(1, 0)

The reason why what you’re trying isn’t working is because && is the boolean AND operator so if you write

User.find_all_by_is_approved(1) && User.find_all_by_is_admin(0)

Both sides of the && here are considered true so this evaluates to the right-hand side i.e. User.find_all_by_is_admin(0)

There is an & (single & sign) operator on arrays in Ruby that gives the intersection of 2 arrays i.e.

User.find_all_by_is_approved(1) & User.find_all_by_is_admin(0)

would be the list of users who are in both lists, but this is an inefficient way of doing it as it results in 2 separate database queries.