Every method for making asynchronous requests returns an [IDBRequest](#idbrequest) object that communicates back to the requesting application through events. This design means that any number of requests can be active on any at a time.

In the following example, we open a asynchronously. Various event handlers are registered for responding to various situations.

request . [result](#dom-idbrequest-result)

When a request is completed, returns the result, or undefined if the request failed. Throws a “[InvalidStateError](https://www.w3.org/TR/WebIDL-1/#invalidstateerror)“ [DOMException](https://www.w3.org/TR/WebIDL-1/#idl-DOMException) if the request is still pending.

request . [error](#dom-idbrequest-error)

When a request is completed, returns the (a [DOMException](https://www.w3.org/TR/WebIDL-1/#idl-DOMException)), or null if the request succeeded. Throws a “[InvalidStateError](https://www.w3.org/TR/WebIDL-1/#invalidstateerror)“ [DOMException](https://www.w3.org/TR/WebIDL-1/#idl-DOMException) if the request is still pending.

Returns the [IDBObjectStore](#idbobjectstore), [IDBIndex](#idbindex), or [IDBCursor](#idbcursor) the request was made against, or null if is was an open request.

request .

Returns the [IDBTransaction](#idbtransaction) the request was made within. If this as an , then it returns an upgrade transaction while it is running, or null otherwise.

request . [readyState](#dom-idbrequest-readystate)

Returns ["pending"](#dom-idbrequestreadystate-pending) until a request is complete, then returns ["done"](#dom-idbrequestreadystate-done).

The result attribute’s getter must an “[InvalidStateError](https://www.w3.org/TR/WebIDL-1/#invalidstateerror)“ [DOMException](https://www.w3.org/TR/WebIDL-1/#idl-DOMException) if the done flag is unset. Otherwise, the attribute’s getter must return the of the request, or undefined if the request resulted in an error.

The error attribute’s getter must throw an “[InvalidStateError](https://www.w3.org/TR/WebIDL-1/#invalidstateerror)“ [DOMException](https://www.w3.org/TR/WebIDL-1/#idl-DOMException) if the is unset. Otherwise, the attribute’s getter must return the error of the request, or null if no error occurred.

The transaction attribute’s getter must return the of the request. This property can be null for certain requests, such as for returned from [open()](#dom-idbfactory-open).

The attribute’s getter must return ["pending"](#dom-idbrequestreadystate-pending) if the done flag is unset, and ["done"](#dom-idbrequestreadystate-done) otherwise.

The onsuccess attribute is the event handler for the success event.

The onerror attribute is the event handler for the error event.

Methods on [IDBDatabase](#idbdatabase) that return a use an extended interface to allow listening to the [blocked](#request-blocked) event and [upgradeneeded](#request-upgradeneeded) event.

The onblocked attribute is the event handler for the [blocked](#request-blocked) event.

The onupgradeneeded attribute is the event handler for the [upgradeneeded](#request-upgradeneeded) event.