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IDBObjectStore.deleteIndex

The deleteIndex() method of the IDBObjectStore interface destroys the index with the specified name in the connected database, used during a version upgrade.

Note that this method must be called only from a VersionChange transaction mode callback. Note that this method synchronously modifies the IDBObjectStore.indexNames property.

Note: This feature is available in Web Workers.

Syntax

objectStore.deleteIndex(indexName);

Parameters

indexName
The name of the existing index to remove.

Return value

undefined

Exceptions

This method may raise a DOMException of one of the following types:

Exception Description
InvalidStateError Occurs if the method was not called from a versionchange transaction mode callback.
TransactionInactiveError Occurs if the transaction this IDBObjectStore belongs to is not active (e.g. has been deleted or removed.) In Firefox previous to version 41, an InvalidStateError was raised in this case as well, which was misleading; this has now been fixed (see bug 1176165.)
NotFoundError Occurs if there is no index with the given name (case-sensitive) in the database.

Example

In the following example you can see the IDBOpenDBRequest.onupgradeneeded handler being used to update the database structure if a database with a higher version number is loaded. IDBObjectStore.createIndex is used to create new indexes on the object store, after which we delete the unneeded old indexes with deleteIndex(). For a full working example, see our To-do Notifications app (view example live.)

var db;

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

// these two event handlers act on the database being opened successfully, or not
DBOpenRequest.onerror = function(event) {
  note.innerHTML += '<li>Error loading database.</li>';
};

DBOpenRequest.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
 
  // store the result of opening the database in the db variable. This is used a lot below
  db = this.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
//it is only implemented in recent browsers
DBOpenRequest.onupgradeneeded = function(event) {
  var db = this.result;
 
  db.onerror = function(event) {
    note.innerHTML += '<li>Error loading database.</li>';
  };

  // Create an objectStore for this database   
  var 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 });

  objectStore.deleteIndex("seconds");
  objectStore.deleteIndex("contact");

};

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 24
24
23 — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
12 16
16
10 — 16
Prefixed
Prefixed Requires the vendor prefix: moz
10
10
partial
15 7
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes
Yes
? — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
25
25
25 — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
Yes 22 22 8 Yes
Yes
? — 7.0
Prefixed
Prefixed Requires the vendor prefix: webkit

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/deleteIndex