pluck

Person.pluck(:name)# SELECT people.name FROM people# => ['David', 'Jeremy', 'Jose']Person.pluck(:id, :name)# SELECT people.id, people.name FROM people# => [[1, 'David'], [2, 'Jeremy'], [3, 'Jose']]Person.distinct.pluck(:role)# SELECT DISTINCT role FROM people# => ['admin', 'member', 'guest']Person.where(age: 21).limit(5).pluck(:id)# SELECT people.id FROM people WHERE people.age = 21 LIMIT 5# => [2, 3]Person.pluck('DATEDIFF(updated_at, created_at)')# SELECT DATEDIFF(updated_at, created_at) FROM people# => ['0', '27761', '173']