files/en-us/web/api/idbobjectstore/index.md
{{APIRef("IndexedDB")}} {{AvailableInWorkers}}
The IDBObjectStore interface of the IndexedDB API represents an object store in a database. Records within an object store are sorted according to their keys. This sorting enables fast insertion, look-up, and ordered retrieval.
null, the application must provide a key for each modification operation.value, and stores the cloned value in the object store. This is for adding new records to an object store.key is an {{domxref("IDBKeyRange")}}.value, and stores the cloned value in the object store. This is for updating existing records in an object store when the transaction's mode is readwrite.This example shows a variety of different uses of object stores, from updating the data structure with {{domxref("IDBObjectStore.createIndex")}} inside an onupgradeneeded function, to adding a new item to our object store with {{domxref("IDBObjectStore.add")}}. For a full working example, see our To-do Notifications app (view example live).
// Let us open our database
const DBOpenRequest = window.indexedDB.open("toDoList", 4);
DBOpenRequest.onsuccess = (event) => {
note.appendChild(document.createElement("li")).textContent =
"Database initialized.";
// store the result of opening the database in db.
db = DBOpenRequest.result;
};
// This event handles the event whereby a new version of
// the database needs to be created Either one has not
// been created before, or a new version number has been
// submitted via the window.indexedDB.open line above
DBOpenRequest.onupgradeneeded = (event) => {
const db = event.target.result;
db.onerror = (event) => {
note.appendChild(document.createElement("li")).textContent =
"Error loading database.";
};
// Create an objectStore for this database
const objectStore = db.createObjectStore("toDoList", {
keyPath: "taskTitle",
});
// define what data items the objectStore will contain
objectStore.createIndex("hours", "hours", { unique: false });
objectStore.createIndex("minutes", "minutes", { unique: false });
objectStore.createIndex("day", "day", { unique: false });
objectStore.createIndex("month", "month", { unique: false });
objectStore.createIndex("year", "year", { unique: false });
objectStore.createIndex("notified", "notified", { unique: false });
note.appendChild(document.createElement("li")).textContent =
"Object store created.";
};
// Create a new item to add in to the object store
const newItem = [
{
taskTitle: "Walk dog",
hours: 19,
minutes: 30,
day: 24,
month: "December",
year: 2013,
notified: "no",
},
];
// open a read/write db transaction, ready for adding the data
const transaction = db.transaction(["toDoList"], "readwrite");
// report on the success of the transaction completing, when everything is done
transaction.oncomplete = (event) => {
note.appendChild(document.createElement("li")).textContent =
"Transaction completed.";
};
transaction.onerror = (event) => {
note.appendChild(document.createElement("li")).textContent =
"Transaction not opened due to error. Duplicate items not allowed.";
};
// create an object store on the transaction
const objectStore = transaction.objectStore("toDoList");
// make a request to add our newItem object to the object store
const objectStoreRequest = objectStore.add(newItem[0]);
objectStoreRequest.onsuccess = (event) => {
note.appendChild(document.createElement("li")).textContent =
"Request successful.";
};
{{Specifications}}
{{Compat}}