Normalized state shape example

state.js

const posts = [
  {title: 'title 1', id: 1231},
  {title: 'title 2', id: 1232},
  {title: 'title 3', id: 1233},
  {title: 'title 4', id: 1234},
  {title: 'title 5', id: 1235},
  {title: 'title 6', id: 1236},
  {title: 'title 7', id: 1237},
  {title: 'title 8', id: 1238},
  {title: 'title 9', id: 1239},
];

const findPost = (postId) posts.find(p => postId === p.id);

const postsById = {
  1231: {title: 'title 1', id: 1231},
  1232: {title: 'title 2', id: 1232},
  1233: {title: 'title 3', id: 1233},
  1234: {title: 'title 4', id: 1234},
  1235: {title: 'title 5', id: 1235}
};

postById["1234"] === postById.1234

const findPostById = (postId) => postsById[postId]
const updatePostById = (postId, post) => postsById[postId] = {...postsById[postId], ...post}