Update data

Update an object in the store

Update an object

Updating an object is the same as setting an object in the store. The only difference here is that the object with that primaryKey already exists in the store.

Here we will add a new user object into the store and then update it.

Read store.mutate(). For more information on dealing with many objects, etc.

example-project/index.js

const userObject = {
  id: 1,
  username: "the_overlord",
}

const getUserOne = () => store.select({ from: "user", fields: ["id", "username"], where: {id: 1} })

store.mutate(userObject);

console.log("Before", getUserOne())

const updatedUser = {
  id: 1,
  username: "Update Name",
}

store.mutate(updatedUser);

console.log("After", getUserOne())

Run node index.js and you should see this in the terminal.

Before { id: 1, username: 'the_overlord' }
After { id: 1, username: 'Update Name' }

Deep Update

If a new object is set in the store, and the object contains a child that already exists, it will be updated if there are changes.

example-project/index.js

import { posts } from "./data.js";

store.mutate(posts);

const getUserOne = () => store.select({ from: "user", fields: ["id", "username"], where: {id: 1} })

console.log("Before", getUserOne())

const updatedPost = {
  id: 8,
  __identify__: "post",
  user: {
    id: 1,
    username: "Updated!"
  }
}

store.mutate(updatedPost);

console.log("After", getUserOne())

Run node index.js and you should see this in the terminal.

Before { id: 1, username: 'the_overlord' }
After { id: 1, username: 'Updated!' }

Update foreign key references

Let's say we have a Post object, the post belongs to User 1 and we want to change it to User 2.

example-project/index.js

import { posts } from "./data.js";

store.mutate(posts);

const getPost = () => store.select({
  from: "post",
  fields: ["id", "user"],
  where: { id: 8 },
  join: [{ on: "user", fields: ["id", "username"] }]
})

console.log("Before", getPost())

const updatedPost = {
  id: 8,
  __identify__: "post",
  user: 2
  // user: {id: 2, __identify__: "user"}
}

store.mutate(updatedPost);

console.log("After", getPost())

Run node index.js and you should see this in the terminal.

Before { id: 8, user: { id: 1, username: 'the_overlord' } }
After { id: 8, user: { id: 2, username: 'qwerty' } }

Remove a foreign key reference

Sometimes we may want to remove a foreign key reference

example-project/index.js

import { posts } from "./data.js";

store.mutate(posts);

const getPost = () => store.select({
  from: "post",
  fields: ["id", "user"],
  where: { id: 8 },
  join: [{ on: "user", fields: ["id", "username"] }]
})

const getUser = () => store.select({
  from: "user",
  fields: ["id", "posts"],
  where: { id: 1 },
})


console.log("Post Before", getPost())
console.log("User Before", getUser())

const updatedPost = {
  id: 8,
  __identify__: "post",
  user: null // set as null to remove the reference
}

store.mutate(updatedPost);

console.log("Post After", getPost())
console.log("User After", getUser())

Run node index.js and you should see this in the terminal.

Post Before { id: 8, user: { id: 1, username: 'the_overlord' } }
User Before { id: 1, posts: [ 8, 7 ] }
Post After { id: 8 }
User After { id: 1, posts: [ 7 ] }

This can also be done the other way around by removing post 7 from user 1

example-project/index.js

import { posts } from "./data.js";

store.mutate(posts);

const getPost = () => store.select({
  from: "post",
  fields: ["id", "user"],
  where: { id: 8 },
  join: [{ on: "user", fields: ["id", "username"] }]
})

const getUser = () => store.select({
  from: "user",
  fields: ["id", "posts"],
  where: { id: 1 },
})


console.log("Post Before", getPost())
console.log("User Before", getUser())

const updatedPost = {
  id: 1,
  __identify__: "user",
  posts: [7] // removing post 8 from user 1
}

store.mutate(updatedPost);

console.log("Post After", getPost())
console.log("User After", getUser())

Run node index.js and you should see this in the terminal.

Post Before { id: 8, user: { id: 1, username: 'the_overlord' } }
User Before { id: 1, posts: [ 8, 7 ] }
Post After { id: 8 }
User After { id: 1, posts: [ 7 ] }