> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sqd.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# drizzleTarget

> PostgreSQL target for Pipes SDK via Drizzle ORM

See the [Postgres via Drizzle guide](../../../guides/basic-development/targets/postgres-drizzle) for usage examples and setup instructions.

```ts theme={"system"}
import { drizzleTarget } from '@subsquid/pipes/targets/drizzle/node-postgres'
```

## `drizzleTarget`

```ts theme={"system"}
drizzleTarget<T>({
  db: NodePgDatabase,
  tables: Table[] | Record<string, Table>,
  onStart?: (ctx: { db: NodePgDatabase }) => Promise<unknown>,
  onData: (ctx: { tx: Transaction; data: T; ctx: Ctx }) => Promise<unknown>,
  onBeforeRollback?: (ctx: { tx: Transaction; cursor: BlockCursor }) => Promise<unknown> | unknown,
  onAfterRollback?: (ctx: { tx: Transaction; cursor: BlockCursor }) => Promise<unknown> | unknown,
  settings?: {
    state?: StateOptions
    transaction?: {
      isolationLevel?: 'read uncommitted' | 'read committed' | 'repeatable read' | 'serializable'
    }
  },
})
```

| Parameter                             | Required | Description                                                                                     |
| ------------------------------------- | -------- | ----------------------------------------------------------------------------------------------- |
| `db`                                  | Yes      | Drizzle `NodePgDatabase` instance. Must expose `$client` (a `pg` Pool or Client).               |
| `tables`                              | Yes      | Tables tracked for automatic fork rollback. All tables written to in `onData` must appear here. |
| `onStart`                             | No       | Runs once before processing starts. Receives `{ db }`.                                          |
| `onData`                              | Yes      | Called for each batch inside a serializable transaction.                                        |
| `onBeforeRollback`                    | No       | Called inside the rollback transaction before snapshots are replayed.                           |
| `onAfterRollback`                     | No       | Called inside the rollback transaction after snapshots are replayed.                            |
| `settings.state`                      | No       | Configuration for the internal cursor state table. See `StateOptions` below.                    |
| `settings.transaction.isolationLevel` | No       | Transaction isolation level. Defaults to `'serializable'`.                                      |

**`StateOptions`:**

| Field                        | Default    | Description                                                           |
| ---------------------------- | ---------- | --------------------------------------------------------------------- |
| `schema`                     | `'public'` | PostgreSQL schema for the state table.                                |
| `table`                      | `'sync'`   | Name of the state table.                                              |
| `id`                         | `'stream'` | Stream identifier within the state table.                             |
| `unfinalizedBlocksRetention` | `1000`     | Number of unfinalized blocks retained in state for rollback purposes. |

## `batchForInsert`

```ts theme={"system"}
import { batchForInsert } from '@subsquid/pipes/targets/drizzle/node-postgres'
```

```ts theme={"system"}
function batchForInsert<T>(data: readonly T[], size?: number): Generator<T[]>
```

Splits an array into chunks that fit within PostgreSQL's 32,767-parameter limit. Chunk size is `Math.floor(32767 / columnsPerRecord)` by default. Pass `size` to set a smaller cap; values exceeding the computed maximum are silently clamped.

`chunk` is a deprecated alias for `batchForInsert`.