IDBObjectStore: createIndex() method

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Widely available

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

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Note: This feature is available in Web Workers.

The createIndex() method of the IDBObjectStore interface creates and returns a new IDBIndex object in the connected database. It creates a new field/column defining a new data point for each database record to contain.

Bear in mind that IndexedDB indexes can contain any JavaScript data type; IndexedDB uses the structured clone algorithm to serialize stored objects, which allows for storage of simple and complex objects.

Note that this method must be called only from a VersionChange transaction mode callback.

Syntax

createIndex(indexName, keyPath)
createIndex(indexName, keyPath, options)

Parameters

indexName

The name of the index to create. Note that it is possible to create an index with an empty name.

keyPath

The key path for the index to use. Note that it is possible to create an index with an empty keyPath, and also to pass in a sequence (array) as a keyPath.

options Optional

An object which can include the following properties:

unique: If true, the index will not allow duplicate values for a single key. Defaults to false.
multiEntry: If true, the index will add an entry in the index for each array element when the keyPath resolves to an array. If false, it will add one single entry containing the array. Defaults to false.
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