Web/API/IDBKeyRange/lowerBound

The lowerBound() method of the IDBKeyRange interface creates a new key range with only a lower bound. By default, it includes the lower endpoint value and is closed.

Note: This feature is available in Web Workers.

Syntax

var myIDBKeyRange = IDBKeyRange.lowerBound(lower);
var myIDBKeyRange = IDBKeyRange.lowerBound(lower, open);

Parameters

lower: specifies the lower bound of the new key range.
open Optional: indicates whether the lower bound excludes the endpoint value. The default is false.

Return value

IDBKeyRange: The newly created key range.

Exceptions

This method may raise a DOMException of the following type:

Exception	Description
DataError	The value parameter passed was not a valid key.

Example

The following example illustrates how you'd use a lower bound key range. Here we declare keyRangeValue = IDBKeyRange.lowerBound("F", false); — a range that includes the value "F" and everthing after it. 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 "F" and all that come after it. If we used IDBKeyRange.lowerBound("F", true);, then the range would not include "F"; only the values after it.

Note: For a more complete example allowing you to experiment with key range, have a look at our IDBKeyRange-example repo ([[../../../../../../../mdn.github.io/indexeddb-examples/idbkeyrange/index|view the example live too]].)

function displayData() {
  var keyRangeValue = IDBKeyRange.lowerBound("F");

  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.');
      }
    };
  };

Specification

Specification	Status	Comment
Indexed Database API 2.0The definition of 'lowerBound()' in that specification.	Recommendation
Indexed Database API DraftThe definition of 'lowerBound()' in that specification.	Recommendation

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`lowerBound`	Chrome Full support 24 Full support 24 No support 23 — 24 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes

Legend

Full support: Full support
Partial support: Partial support
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.