IndexedDBtä

IndexedDBtä is not a term found in official web specifications; this article describes IndexedDB, the standard client-side storage API, using IndexedDBtä as a contextual variant only.

IndexedDB is a low-level API for storing significant amounts of structured data in a web browser. It operates asynchronously and is designed for offline-capable web applications. Data is stored in a database that persists within the origin and is organized into object stores, which hold records identified by keys. Keys can be simple values or derived from a keyPath, and object stores can define indexes to support efficient queries. Databases have version numbers and can be upgraded to modify their schema.

The API is based on requests and events. A database is opened with indexedDB.open(name, version). The resulting request exposes events such as onsuccess, onerror, and onupgradeneeded. In a running application, operations occur within transactions, which can be readonly or readwrite. Within a transaction, code can access one or more object stores and perform actions such as add, put, get, getAll, delete, and clear. openCursor enables iteration over records and range queries.

Transactions provide atomicity and isolation: all operations within a single transaction either complete together or fail together. A single upgrade transaction (triggered by a version change) can create or modify object stores and indexes. Data remains scoped to the origin and is subject to browser storage quotas and privacy considerations.

Common use cases include offline data caching, large client-side datasets, and apps requiring complex queries beyond simple key-value storage. To simplify development, developers often use wrapper libraries that provide promise-based APIs over the native event-driven interface.