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ruby on rails - How to get a single column's values into an array

Right now I'm doing something like this to select a single column of data:

points = Post.find_by_sql("select point from posts")

Then passing them to a method, I'd like my method to remain agnostic, and now have to call hash.point from within my method. How can I quickly convert this into an array and pass the data set to my method, or is there a better way?

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In Rails 3.2 there is a pluck method for this

Just like this:

Person.pluck(:id) # SELECT people.id FROM people
Person.pluck(:role).uniq # unique roles from array of people
Person.distinct.pluck(:role) # SELECT DISTINCT role FROM people SQL
Person.where(:confirmed => true).limit(5).pluck(:id)

Difference between uniq and distinct


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