Easily remember ManyToMany ManyToOne OneToMany

ManyToMany in a Person <> Blog Relationship
A Person can be a subscriber of many blogs.
A Blog can have many subscribers.

const Person = {
  isSubscriberOfBlogs: []
}
const Blog = {
  subscribers = []
}

const Person = {

isSubscriberOfBlogs: []

}

const Blog = {

subscribers = []

}

But since this is an inefficient way to manage usually a proxy table is used with [PersonID], [BlogID], aka the 2 related data models.

ManyToOne and OneToMany in a Person <> Blog Relationship
A Person can be the owner of many Blogs.
A Blog can have one owner Person.

const Person = {
  id: 1
  isOwnerOfBlogs: [10, 20] // OneToMany
}
const BlogA = {
  id: 10,
  owner_id: 1 // ManyToOne
}
const BlogA = {
  id: 20,
  owner_id: 1 // ManyToOne
}

const Person = {

id: 1

isOwnerOfBlogs: [10, 20] // OneToMany

}

const BlogA = {

id: 10,

owner_id: 1 // ManyToOne

}

const BlogA = {

id: 20,

owner_id: 1 // ManyToOne

}

In conclusion, ToMany means it’s an array, ToOne means it’s a single value.

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