# std-toolkit/db/idb

IndexedDB adapter that realizes a StdTable on a reusable in-browser database connection.

## Big picture

IDB implements the StdTable contract on top of one IndexedDB database. Each StdTable becomes an object store with indexes for its secondary indexes. Setup is explicit and performs the versioned store and index upgrade; providing the layer never runs it. Divergences from the DynamoDB topology are in [CONTEXT.md](CONTEXT.md); the shared vocabulary is in [db/CONTEXT.md](../CONTEXT.md). The browser sync preset uses this adapter for its Sync Store.

## Install

See the [top README](../../../README.md).

## Exports

### `std-toolkit/db/idb`

| Export         | What it does                                                                              |
| -------------- | ----------------------------------------------------------------------------------------- |
| `IDB.make`     | Realizes a StdTable on a database connection; returns `storeName`, `layer`, and `setup`.  |
| `IDB.database` | Returns a reusable connection to a named IndexedDB database, cached per name and factory. |

## Usage

### Run a program on IndexedDB

Lifted from story 24.

```ts
import { Effect } from 'effect';
import { StdTable } from 'std-toolkit/db';
import { IDB } from 'std-toolkit/db/idb';

const table = StdTable.make('board').primary('pk', 'sk').build();

const idb = IDB.make(table, {
  database: IDB.database({ databaseName: 'board' }),
});

const program = Effect.gen(function* () {
  yield* idb.setup;
  return yield* saveAndRead.pipe(Effect.provide(idb.layer));
});
```

- One `IDB.database` connection can serve several StdTables; each gets its own store.
- Pass `indexedDB` in the database config to use a different factory, such as `fake-indexeddb` in tests.
- `storeName` defaults to the table's logical name.