Rails Model find where not equal

In Rails 4.x (See http://edgeguides.rubyonrails.org/active_record_querying.html#not-conditions)

GroupUser.where.not(user_id: me)

In Rails 3.x

GroupUser.where(GroupUser.arel_table[:user_id].not_eq(me))

To shorten the length, you could store GroupUser.arel_table in a variable or if using inside the model GroupUser itself e.g., in a scope, you can use arel_table[:user_id] instead of GroupUser.arel_table[:user_id]

_{Rails 4.0 syntax credit to @jbearden’s answer}