Reading and writing

Each collection is available as db.<name>, with methods for reading and writing single records or batches.

const id = await db.users.insert({ name: 'Ali', email: 'ali@example.com', age: 30, tags: ['admin'] })
await db.users.insertMany([sara, reza]) // atomic: all or nothing

const user = await db.users.get(id) // User | undefined
const some = await db.users.getMany([1, 2, 3]) // (User | undefined)[]
const all = await db.users.toArray()
const total = await db.users.count()

await db.users.update(id, { name: 'Ali R.' }) // merge a patch; false if the record is missing
await db.users.update(id, (u) => ({ ...u, tags: [...u.tags, 'dev'] }))
await db.users.put({ id, name: 'Ali', email: 'ali@example.com', age: 30, tags: [] }) // insert or replace
await db.users.delete(id)
await db.users.clear()

await db.settings.insert({ value: 'dark' }, 'theme') // out-of-line key
await db.settings.get('theme')

What to expect

• Writes resolve after the transaction commits. insert and put resolve with the key.
• insertMany and putMany run in one transaction: either every record is written, or none is.
• insert rejects with the code Constraint when the key or a unique index value already exists. put replaces the record with the same key instead.
• update resolves with false when there is no record with that key, and does not create one.
• Keys are type-sensitive: 1 and '1' are different keys.

What can be stored

Values are stored with the browser's structured clone algorithm. Plain objects, arrays, Date, Map, Set, Blob, File and typed arrays work. Functions, class methods, DOM nodes and framework proxies do not; storing them rejects with the code DataClone. With Vue or MobX, store plain data (see SSR, frameworks and tests).

To write to several collections at once, all or nothing, use a transaction.