IDBDatabase
===========

The **`IDBDatabase`** interface of the IndexedDB API provides a connection to a database; you can use an `IDBDatabase` object to open a transaction on your database then create, manipulate, and delete objects (data) in that database. The interface provides the only way to get and manage versions of the database.

**Note:** This feature is available in Web Workers

**Note:** Everything you do in IndexedDB always happens in the context of a transaction, representing interactions with data in the database. All objects in IndexedDB — including object stores, indexes, and cursors — are tied to a particular transaction. Thus, you cannot execute commands, access data, or open anything outside of a transaction.

EventTarget

IDBDatabaseInstance properties
-------------------

`IDBDatabase.name` Read only 

A string that contains the name of the connected database.

`IDBDatabase.version` Read only 

A 64-bit integer that contains the version of the connected database. When a database is first created, this attribute is an empty string.

`IDBDatabase.objectStoreNames` Read only 

A `DOMStringList` that contains a list of the names of the object stores currently in the connected database.

Instance methods
----------------

Inherits from: EventTarget

`IDBDatabase.close()`

Returns immediately and closes the connection to a database in a separate thread.

`IDBDatabase.createObjectStore()`

Creates and returns a new object store or index.

`IDBDatabase.deleteObjectStore()`

Destroys the object store with the given name in the connected database, along with any indexes that reference it.

`IDBDatabase.transaction()`

Immediately returns a transaction object (`IDBTransaction`) containing the `IDBTransaction.objectStore` method, which you can use to access your object store. Runs in a separate thread.

Events
------

Listen to these events using `addEventListener()` or by assigning an event listener to the `oneventname` property of this interface.

`close`

An event fired when the database connection is unexpectedly closed.

`versionchange`

An event fired when a database structure change was requested.

The following events are available to `IDBDatabase` via event bubbling from `IDBTransaction`:

`IDBTransaction` `abort`

An event fired when a transaction is aborted.

`IDBTransaction` `error`

An event fired when a request returns an error and the event bubbles up to the connection object.

Example
-------

In the following code snippet, we open a database asynchronously (`IDBFactory`), handle success and error cases, and create a new object store in the case that an upgrade is needed (`IDBdatabase`). For a complete working example, see our To-do Notifications app (view example live).


```js
// Let us open our database
const DBOpenRequest = window.indexedDB.open("toDoList", 4);

// these two event handlers act on the IDBDatabase object,
// when the database is opened successfully, or not
DBOpenRequest.onerror = (event) => {
  note.innerHTML += "<li>Error loading database.</li>";
};

DBOpenRequest.onsuccess = (event) => {
  note.innerHTML += "<li>Database initialized.</li>";

  // store the result of opening the database in the db
  // variable. This is used a lot later on
  db = DBOpenRequest.result;

  // Run the displayData() function to populate the task
  // list with all the to-do list data already in the IDB
  displayData();
};

// 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.innerHTML += "<li>Error loading database.</li>";
  };

  // Create an objectStore for this database using
  // IDBDatabase.createObjectStore

  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.innerHTML += "<li>Object store created.</li>";
};
```


This next line opens up a transaction on the Database, then opens an object store that we can then manipulate the data inside of.


```js
const objectStore = db
  .transaction("toDoList", "readwrite")
  .objectStore("toDoList");
```

Specifications
--------------

| Specification |
| --- |
| Indexed Database API 3.0 # database-interface |

Browser compatibility
---------------------

BCD tables only load in the browser with JavaScript enabled. Enable JavaScript to view data.

See also
--------

* Using IndexedDB
* Starting transactions: `IDBDatabase`
* Using transactions: `IDBTransaction`
* Setting a range of keys: `IDBKeyRange`
* Retrieving and making changes to your data: `IDBObjectStore`
* Using cursors: `IDBCursor`
* Reference example: To-do Notifications (View the example live).