IDBObjectStore: deleteIndex() method
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.
Syntax
Parameters
-
indexName
-
The name of the existing index to remove.
Return value
Exceptions
InvalidStateError
DOMException
-
Thrown if the method was not called from a versionchange
transaction mode callback.
TransactionInactiveError
DOMException
-
Thrown if the transaction this IDBObjectStore
belongs to is not active (e.g. has been deleted or removed.)
NotFoundError
DOMException
-
Thrown if there is no index with the given name (case-sensitive) in the database.
Examples
In the following example you can see the 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).
let db;
const DBOpenRequest = window.indexedDB.open("toDoList", 4);
DBOpenRequest.onerror = (event) => {
note.innerHTML += "<li>Error loading database.</li>";
};
DBOpenRequest.onsuccess = (event) => {
note.innerHTML += "<li>Database initialized.</li>";
db = event.target.result;
displayData();
};
DBOpenRequest.onupgradeneeded = (event) => {
const db = event.target.result;
db.onerror = (event) => {
note.innerHTML += "<li>Error loading database.</li>";
};
const objectStore = db.createObjectStore("toDoList", {
keyPath: "taskTitle",
});
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 compatibility
|
Desktop |
Mobile |
|
Chrome |
Edge |
Firefox |
Internet Explorer |
Opera |
Safari |
WebView Android |
Chrome Android |
Firefox for Android |
Opera Android |
Safari on IOS |
Samsung Internet |
deleteIndex |
23 |
12 |
10 |
10 |
15 |
8 |
4.4 |
25 |
22 |
14 |
8 |
1.5 |
See also