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

js
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

Enable JavaScript to view this browser compatibility table.

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This page was last modified on Jul 26, 2024 by MDN contributors.

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