Find/Remove ActiveRecord older than n days

find_remove_old_activerecord.rb

# Get objects older than 3 days.
@models = MyModel.where('created_at < :time', { time: 3.days.ago })
@models = MyModel.where(['created_at < ?', 3.days.ago])

# Get objects within the last 3 days.
@models = MyModel.where('created_at >= :time', { time: 3.days.ago })
@models = MyModel.where(['created_at >= ?', 3.days.ago])

# Multiple conditions.
@models = MyModel.where(['created_at >= ? and name like ?', 3.days.ago, 'Sam%'])

# Destroy objects older than 3 days.
MyModel.destroy_all(['created_at < ?', 3.days.ago])