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

For Mysql, your can use group with ONLY_FULL_GROUP_BY disabled,

Item.group(:name).to_sql
=> "SELECT `items`.* FROM `items`  GROUP BY name"

See Is there ANY_VALUE capability for mysql 5.6?