---
title: Index Stores
---

Index stores are underlying storage components that contain metadata(i.e. information created when indexing) about the [index](/docs/llamaindex/modules/data/data_index) itself.

## Available Index Stores

- [SimpleIndexStore](/docs/api/classes/SimpleIndexStore): A simple in-memory index store with support for [persisting](/docs/llamaindex/modules/data/stores#local-storage) data to disk.
- [PostgresIndexStore](/docs/api/classes/PostgresIndexStore): A PostgreSQL index store, , see [PostgreSQL Storage](/docs/llamaindex/modules/data/stores#postgresql-storage).

Check the [LlamaIndexTS Github](https://github.com/run-llama/LlamaIndexTS) for the most up to date overview of integrations.

## Using PostgreSQL as Index Store

```package-install
npm i llamaindex @llamaindex/postgres
```

You can configure the `schemaName`, `tableName`, `namespace`, and
`connectionString`. If a `connectionString` is not
provided, it will use the environment variables `PGHOST`, `PGUSER`,
`PGPASSWORD`, `PGDATABASE` and `PGPORT`.

```typescript
import { Document, VectorStoreIndex, storageContextFromDefaults } from "llamaindex";
import { PostgresIndexStore } from "@llamaindex/postgres";

const storageContext = await storageContextFromDefaults({
  indexStore: new PostgresIndexStore(),
});
```

## API Reference

- [BaseIndexStore](/docs/api/classes/BaseIndexStore)
