These snippets show how to work with putting objects into the IndexedDB database, not just simple string key/values

indexeddb-objects-in-object-store.js

// Offline Web Applications course on Udacity https://classroom.udacity.com/courses/ud899

//This should all go into an indexed-db index.js file
//Again, idb is a plugin used to make working with IndexedDB easier

//Difference between this and https://gist.github.com/luke-denton/55be283cbddf6f0c0d362fd95fc9280a, version has been upgraded
var dbPromise = idb.open('test-db', 2, function() {
  switch(upgradeDb.oldVersion)
    case 0:
      var keyValStore = upgradeDb.createObjectStore('keyval');
      keyValStore.put("world", "hello");
      //No break; here, so that if a user comes with a much older database, they'll get all updates in order.
      //Or, if they only need the very newest one, they'll jump straight to that point in the code
    case 1:
      upgradeDb.createObjectStore('people', { keypath: 'name' });
    case 2:
      //For grouping together using indexes
      var peopleStore = upgradeDb.transaction.objectStore('people');
      peopleStore.createIndex('superhero', 'favoriteSuperhero');
})

//Add some data to the new object store
dbPromise.then(function(db) {
  var tx = db.transaction('people', 'readwrite');
  var peopleStore = tv.objectStore('people');
  
  peopleStore.put({
    name: 'Suzanne	Norman',
    age: 25,
    favoriteSuperhero: 'wonder woman'
  });
  
  return tx.complete
}).then(function() {
  console.log("People added!");
});

//Read data from the datastore
dbPromise.then(function(db) {
  var tx = db.transaction('people');
  var peopleStore = tx.objectStore('people');
  
  return peopleStore.getAll();
}).then(function(people) {
  console.log(people);
});

//Group data together using indexes
dbPromise.then(function(db) {
  var tx = db.transaction('people');
  var peopleStore = tx.objectStore('people');
  var superheroIndex = peopleStore.index('superhero');
  
  return superheroIndex.getAll();
}).then(function(people) {
  console.log(people);
});

//Query the data
//Only get people who's favourite superhero is Superman
dbPromise.then(function(db) {
  var tx = db.transaction('people');
  var peopleStore = tx.objectStore('people');
  var superheroIndex = peopleStore.index('superhero');
  
  return superheroIndex.getAll('superman'); //Pass the filter value into the getAll() function
}).then(function(people) {
  console.log(people);
});