Rails 4 query unique by single attribute

Question

So this is more of an arel question than anything but here\'s what I am trying to do.

I have three objects lets say, called Items

Answer 1

If you only need an array with the names, without the ID, you can do:

Item.pluck(:name).uniq

SQL query result:

#=> SELECT `items`.`name` FROM `items`

** edit **

The uniq is ran on the array of records. Be careful if you expect a lot of records. SQL Distinct is much faster.

If so, use vee's answer above, with a map:

Item.select('distinct name').map(:name)