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IDBFactory: cmp() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

Note: This feature is available in Web Workers.

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.

Syntax

cmp(first, second)

Parameters

first: The first key to compare.
second: The second key to compare.

Return value

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

Exceptions

DataError DOMException: Thrown if one of the supplied keys was not a valid key.

Examples

const a = 1;
const b = 2;
const result = window.indexedDB.cmp(a, b);
console.log(`Comparison results: ${result}`);

Specifications

Specification
Indexed Database API 3.0> # ref-for-dom-idbfactory-cmp①>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`cmp`	23	12	10	15	8	25	22	14	8	1.5	4.4	8