What is ActiveRecord equivalence in the node.js world?

Waterline seems to be the thing that you're looking for. It was created by the same guys behind the Sails Project.

https://github.com/balderdashy/waterline

Updated answer

Use sequelize

Old answer:

Look at the Tower project. You can define your models as follows:

# app/models/user.coffeeclass App.User extends Tower.Model  @belongsTo "author", type: "User"  @belongsTo "commentable", polymorphic: true  @has_many "topics"  @has_many "friends"  @has_many "friend_users", through: "friends"  @has_many "friend_topics", through: "friends_users", source: "topics"# app/models/friend.coffeeclass App.Friend extends Tower.Model  @belongs_to "user"  @belongs_to "friend_user", type: "User",                 foreign_key: "phone_no", primary_key: "phone_no"# app/models/topic.coffeeclass App.Topic extends Tower.Model  @belongs_to "user"

Now you will be able to query your data as

current_user.friend_topics().limit(10)

If you are using MySql, you can try Sequelize.js.It's hard to reach the number of features that ActiveRecord offers, but nevertheless, I have been working with Sequelize and its a nice solution for Node.js

There are several other ORM solutions for other DB, you can check them here http://search.npmjs.org/