> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify-poc.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# chunking_recursive_character_text_splitter()

> Recursively split text using multiple separators for better semantic preservation

Recursively split text into chunks using multiple separators. This provides more fine-grained control over the
chunking process and can better preserve semantic meaning by trying separators in order.

The function tries each separator in order. If a chunk is still too large after applying a separator, it tries the
next separator in the list. This helps preserve natural text boundaries like paragraphs and sentences.

You use this function to:

* Recursively split text using multiple separators
* Preserve more semantic meaning in chunks
* Try separators in order (paragraphs, then sentences, then words)
* Default configuration balances context preservation and chunk size

## Samples

### Default recursive splitting

Use the default separator hierarchy:

```sql theme={"dark"}
SELECT ai.create_vectorizer(
    'blog_posts'::regclass,
    loading => ai.loading_column('content'),
    embedding => ai.embedding_openai('text-embedding-3-small', 768),
    chunking => ai.chunking_recursive_character_text_splitter()
);
```

### Custom chunk size and overlap

```sql theme={"dark"}
SELECT ai.create_vectorizer(
    'documents'::regclass,
    loading => ai.loading_column('content'),
    embedding => ai.embedding_openai('text-embedding-3-small', 768),
    chunking => ai.chunking_recursive_character_text_splitter(256, 20)
);
```

### Custom separator hierarchy

Try newlines first, then spaces:

```sql theme={"dark"}
SELECT ai.create_vectorizer(
    'text_data'::regclass,
    loading => ai.loading_column('text'),
    embedding => ai.embedding_openai('text-embedding-3-small', 768),
    chunking => ai.chunking_recursive_character_text_splitter(
        chunk_size => 512,
        chunk_overlap => 50,
        separators => array[E'\n\n', E'\n', ' ', '']
    )
);
```

## Arguments

| Name                 | Type     | Default                                         | Required | Description                                         |
| -------------------- | -------- | ----------------------------------------------- | -------- | --------------------------------------------------- |
| `chunk_size`         | `int`    | `800`                                           | ✖        | Maximum number of characters per chunk              |
| `chunk_overlap`      | `int`    | `400`                                           | ✖        | Number of characters to overlap between chunks      |
| `separators`         | `text[]` | `array[E'\n\n', E'\n', '.', '?', '!', ' ', '']` | ✖        | Array of separators to try in order                 |
| `is_separator_regex` | `bool`   | `false`                                         | ✖        | Set to `true` if separators are regular expressions |

## Returns

A JSON configuration object for use in [`create_vectorizer()`][create_vectorizer].

## Related functions

* [`chunking_character_text_splitter()`][chunking_character]: simpler single-separator splitting
* [`chunking_none()`][chunking_none]: disable chunking

[chunking_character]: /api-reference/pgai/vectorizer/chunking_character_text_splitter

[chunking_none]: /api-reference/pgai/vectorizer/chunking_none

[create_vectorizer]: /api-reference/pgai/vectorizer/create_vectorizer