IDBKeyRange.only()

The only() method of the IDBKeyRange interface creates a new key range containing a single value.

Note:

This feature is available in Web Workers.

Syntax

var myIDBKeyRange = IDBKeyRange.only(value);

Parameters

value is the value for the new key range.

Return value

IDBKeyRange: The newly created key range.

Exceptions

This method may raise a DOMException of the following types:

Exception Description
DataError

The value parameter passed was not a valid key.

Example

The following example illustrates how you'd use an only key range. Here we declare a keyRangeValue = IDBKeyRange.only("A"); — a range that only includes the value "A". We open a transaction (using IDBTransaction) and an object store, and open a Cursor with IDBObjectStore.openCursor, declaring keyRangeValue as its optional key range value. This means that the cursor will only retrieve the record with the key value "A".

Note: For a more complete example allowing you to experiment with key range, have a look at our IDBKeyRange repo (view the example live too.)

function displayData() {
  var keyRangeValue = IDBKeyRange.only("A");

  var transaction = db.transaction(['fThings'], 'readonly');
  var objectStore = transaction.objectStore('fThings');

  objectStore.openCursor(keyRangeValue).onsuccess = function(event) {
    var cursor = event.target.result;
      if(cursor) {
        var listItem = document.createElement('li');
        listItem.innerHTML = '<strong>' + cursor.value.fThing + '</strong>, ' + cursor.value.fRating;
        list.appendChild(listItem);

        cursor.continue();
      } else {
        console.log('Entries all displayed.');
      }
    };
  };

Specifications

Specification Status Comment
Indexed Database API 2.0
The definition of 'only' in that specification.
Recommendation
Indexed Database API 2.0
The definition of 'only' in that specification.
Recommendation

Browser compatibility

BCD tables only load in the browser

See also