The cmp()
method of the IDBFactory
interface compares two values as keys to determine equality and ordering for IndexedDB operations, such as storing and iterating.
Note: Do not use this method for comparing arbitrary JavaScript values, because many JavaScript values are either not valid IndexedDB keys (booleans and objects, for example) or are treated as equivalent IndexedDB keys (for example, since IndexedDB ignores arrays with non-numeric properties and treats them as empty arrays, so any non-numeric arrays are treated as equivalent). This throws an exception if either of the values is not a valid key.
var result = indexedDB.cmp(first, second);
An integer that indicates the result of the comparison; the table below lists the possible values and their meanings:
Returned value | Description |
---|---|
-1 | 1st key is less than the 2nd key |
0 | 1st key is equal to the 2nd key |
1 | 1st key is greater than the 2nd key |
This method may raise a DOMException
of the following types:
Attribute | Description |
---|---|
DataError | One of the supplied keys was not a valid key. |
var a = 1; var b = 2; var result = window.indexedDB.cmp(a, b); console.log( "Comparison results: " + result );
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'cmp()' in that specification. | Recommendation | |
Indexed Database API 2.0 The definition of 'cmp()' in that specification. | Recommendation |
Desktop | ||||||
---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
Basic support | 24
|
12 | 16
|
10
|
15 | 7 |
Mobile | |||||||
---|---|---|---|---|---|---|---|
Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
Basic support | Yes
|
25 | Yes | 22 | 22 | 8 | Yes |
IDBDatabase
IDBTransaction
IDBKeyRange
IDBObjectStore
IDBCursor
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBFactory/cmp