web.storage interfaces.

The IDBCursor interface of the IndexedDB API represents a cursor
traversing or iterating over multiple records in a database.

The IDBCursorWithValue interface of the IndexedDB API represents
cursor for traversing or iterating over multiple records in a
It is the same as the `web.storage.IDBCursor`, except that it
the value property.

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

IDBDatabase Events.

The IDBEnvironment helper of the IndexedDB API contains the indexedDB
which provides access to IndexedDB functionality. It is the top
IndexedDB interface implemented by the `window` and `web.workers.Worker`

In the following code snippet, we make a request to open a database,
include handlers for the success and error cases. For a full
example, see our To-do Notifications app (view example live.)

IDBIndex interface of the IndexedDB API provides asynchronous
to an index in a database. An index is a kind of object store
looking up records in another object store, called the referenced
store. You use this interface to retrieve data.

A key range can be a single value or a range with upper and lower
or endpoints. If the key range has both upper and lower bounds,
it is bounded; if it has no bounds, it is unbounded. A bounded
range can either be open (the endpoints are excluded) or closed
endpoints are included). To retrieve all keys within a certain
you can use the following code constructs:

Also inherits methods from its parents `web.storage.IDBRequest`
`web.EventTarget`.

IDBOpenDBRequest Events.

The request object does not initially contain any information
the result of the operation, but once information becomes available,
event is fired on the request, and the information becomes available
the properties of the IDBRequest instance.

IDBRequest Events.

Note that as of Firefox 40, IndexedDB transactions have relaxed
guarantees to increase performance (see bug 1112702.) Previously
a readwrite transaction `IDBTransaction.oncomplete` was fired
when all data was guaranteed to have been flushed to disk. In
40+ the complete event is fired after the OS has been told to
the data but potentially before that data has actually been flushed
disk. The complete event may thus be delivered quicker than before,
there exists a small chance that the entire transaction will
lost if the OS crashes or there is a loss of system power before
data is flushed to disk. Since such catastrophic events are rare
consumers should not need to concern themselves further.

IDBTransaction Events.

The IDBVersionChangeEvent interface of the IndexedDB API indicates
the version of the database has changed, as the result of an
event handler function.

The NavigatorStorage mixin adds to the `web.performance.Navigator`
`web.workers.WorkerNavigator` interfaces the `Navigator.storage`
which provides access to the `web.storage.StorageManager` singleton
for controlling the persistence of data stores as well as obtaining

The Storage interface of the Web Storage API provides access
a particular domain's session or local storage. It allows, for
the addition, modification, or deletion of stored data items.

The StorageEstimate dictionary is used by the `web.storage.StorageManager`
provide estimates of the size of a site's or application's data
and how much of it is in use. The `estimate()` method returns
object that conforms to this dictionary when its `js.Promise`

A StorageEvent is sent to a window when a storage area it has
to is changed within the context of another document.

The StorageManager interface of the the Storage API provides
interface for managing persistance permissions and estimating
storage. You can get a reference to this interface using either
or `WorkerNavigator.storage`.

The storageQuota property of the `web.performance.Navigator`
of the Quota Management API provides means to query and request
usage and quota information.