In this article, you will learn how to use order in Ruby on Rails.
How to use order
The order method in Rails is used to sort the records of a model in a specific order. It takes one or more arguments to specify the order of sorting. Here are some examples of how to use the order method in Rails:
Sort records in ascending order based on a single attribute:
# Get all users sorted by their name in ascending order @users = User.order(:name)
Sort records in descending order based on a single attribute:
# Get all users sorted by their name in descending order @users = User.order(name: :desc)
Sort records based on multiple attributes:
# Get all users sorted by their age in ascending order and then by their name in descending order @users = User.order(age: :asc, name: :desc)
Sort records based on an associated model:
# Get all posts sorted by the title of the associated author in ascending order @posts = Post.includes(:author).order('authors.name ASC')
In this example, includes is used to eager-load the associated author model to avoid the N+1 query problem.
Sort records based on a custom SQL expression:
# Get all products sorted by the sum of their sales in descending order @products = Product.order('SUM(sales) DESC')
In this example, a custom SQL expression is used to calculate the sum of sales for each product and sort the records based on the result.