---
title: "What is a document column?"
description: "A document column stores a PDF or similar file so pages and passages can be split, embedded, and cited from the row."
url: "https://pixeltable.com/learn/what-is-a-document-column"
updated: "2026-09-29"
vertical: "Multimodal data"
doc: "https://docs.pixeltable.com/datastore/computed-columns"
---

# What is a document column?

A document column stores a PDF or similar file so pages and passages can be split, embedded, and cited from the row.

Updated: 2026-09-29
Part of [What is a typed media column?](https://pixeltable.com/learn/what-is-a-typed-media-column).

## On this page

- [How it works](https://pixeltable.com/learn/what-is-a-document-column#how-it-works)
- [What it is not](https://pixeltable.com/learn/what-is-a-document-column#what-it-is-not)
- [Comparison](https://pixeltable.com/learn/what-is-a-document-column#comparison)
- [Where Pixeltable fits](https://pixeltable.com/learn/what-is-a-document-column#where-pixeltable-fits)
- [Questions](https://pixeltable.com/learn/what-is-a-document-column#questions)

## How it works {#how-it-works}


- The file stays addressable after you split it.
- A view emits one row per passage or page and points back at the file.
- Answers can cite the passage because the source row still exists.

## What it is not {#what-it-is-not}

It is not pasted text in a string field, and it is not a blob the engine cannot page.

## document column: this, and the thing it is confused with {#comparison}

|  | This | Not this |
| --- | --- | --- |
| Stored | The file, typed as a document | Text pasted into a string |
| Child rows | Passages or pages | A single vector for the whole file |
| Citation | A pointer back to the file | A chat window with no source |

## Where Pixeltable fits {#where-pixeltable-fits}

Pixeltable types it as pxt.Document. A document-splitter view is how passages stay tied to the file.

## Questions {#questions}

### How does document column work? {#faq-1}

The file stays addressable after you split it. A view emits one row per passage or page and points back at the file. Answers can cite the passage because the source row still exists.

### What is document column often confused with? {#faq-2}

It is not pasted text in a string field, and it is not a blob the engine cannot page.

## In the blog

- [MedDossier: Clinical Intake on One Audio + PDF + Image Row](https://pixeltable.com/blog/meddossier-clinical-intake-triage)
- [ClaimBot: FNOL Triage on One Heterogeneous Row](https://pixeltable.com/blog/claimbot-multimodal-fnol-triage)
- [Build Production Document RAG Pipelines with Pixeltable](https://pixeltable.com/blog/document-pdf-processing-rag-pixeltable)
- [Beyond Pandas: Why Pixeltable Is the Ultimate Tool for Multimodal Data Wrangling](https://pixeltable.com/blog/pixeltable-vs-pandas-multimodal-data-wrangling)
- [DocuVision: PDF Q&A Without LangChain Plus a Vector DB](https://pixeltable.com/blog/docuvision-pdf-chart-qa)

## Related

- [Documentation](https://docs.pixeltable.com/datastore/computed-columns)
- [Build Production Document RAG Pipelines with Pixeltable](https://pixeltable.com/blog/document-pdf-processing-rag-pixeltable)
- [Production RAG](https://pixeltable.com/use-cases/production-rag-implementation)
- [pdf-to-text](https://pixeltable.com/tools/pdf-to-text)
- [chat-with-pdf](https://pixeltable.com/tools/chat-with-pdf)