Get random collection of records with Active Record

Suppose you have a Reminder model and you want to return x number of records at random. Something like this:

Reminder.sample # 1 record
Reminder.sample(5) # 5 records

Here’s how:

class Note
  def self.sample(count = 1)
    find(pluck(:id)).sample(count)
  end
end

This will produce two SQL queries. Something like:

Reminder Pluck (1.2ms)  SELECT "reminders"."id" FROM "reminders"
Reminder Load (0.4ms)  SELECT "reminders".* FROM "reminders" WHERE "reminders"."id" IN ($1, $2)  [["id", 114], ["id", 118]]

Tagged: Rails

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