How does ActiveRecord even work?

Question

Ruby on Rails

Looked at an example of a command to delete an entry from Ruby

user = User.find_by(name: 'David')
user.destroy

I have not found any normal content describing the general AR interface (what methods and how they are used)
Is it necessary to look for an entry and only then delete it? Or is it easier?
user = User.destroy(name: 'David')

Answer 1

user = User.destroy(name: 'David')
why assign the object to be deleted to a variable?
usually done like this:
User.find_by(name: 'David').destroy
or if you need to delete all records where name: 'David' :
User.where(name: 'David').destroy_all
documentation is full on the basics of AR, including .h. and in Russian

Answer 2

Why, did Roskomnadzor ban the documentation?
devdocs.io/rails~4.2/activerecord/relation#method-...