---
title: "What is PDF RAG?"
description: "PDF RAG keeps the file, splits it into passages or pages, embeds those units, and generates an answer that can cite them."
url: "https://pixeltable.com/learn/what-is-pdf-rag"
updated: "2026-09-29"
vertical: "Documents"
doc: "https://docs.pixeltable.com/datastore/computed-columns"
---

# What is PDF RAG?

PDF RAG keeps the file, splits it into passages or pages, embeds those units, and generates an answer that can cite them.

Updated: 2026-09-29
Part of [What is RAG?](https://pixeltable.com/learn/what-is-rag).

## On this page

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

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


- Store the PDF as a document.
- Split it into passages that point back at the file.
- Embed the passages and answer from the nearest ones.

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

It is not uploading a PDF into a chat window with no index, and it is not OCR with nowhere to retrieve from.

## PDF RAG: this, and the thing it is confused with {#comparison}

|  | This | Not this |
| --- | --- | --- |
| Source | The PDF row | A chat attachment that disappears |
| Units | Passages or pages | One vector for the whole file |
| Answer | Cites a passage | Paraphrases with no pointer |

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

Pixeltable stores the document, splits it with a view, and indexes the passage text. The model call reads those hits.

## Questions {#questions}

### How does PDF RAG work? {#faq-1}

Store the PDF as a document. Split it into passages that point back at the file. Embed the passages and answer from the nearest ones.

### What is PDF RAG often confused with? {#faq-2}

It is not uploading a PDF into a chat window with no index, and it is not OCR with nowhere to retrieve from.

## In the blog

- [LectureSync: Slide-Grounded Lecture Q&A Without an Aligner Service](https://pixeltable.com/blog/lecturesync-slide-lecture-qa)
- [DocuVision: PDF Q&A Without LangChain Plus a Vector DB](https://pixeltable.com/blog/docuvision-pdf-chart-qa)
- [Production RAG Systems: Building Data-Centric RAG Applications at Scale](https://pixeltable.com/blog/production-rag-data-centric)
- [Pixeltable vs LangChain for RAG Systems: Comprehensive Comparison for AI Infrastructure](https://pixeltable.com/blog/pixeltable-vs-langchain-rag-comparison)
- [Pixeltable vs Pinecone: When You Need a Vector Database vs Unified AI Infrastructure](https://pixeltable.com/blog/pixeltable-vs-pinecone-vector-database-comparison)
- [The @pxt.query Decorator: Building Reusable Database Queries for AI Agents and RAG Systems](https://pixeltable.com/blog/reusable-query-patterns-pxt-query)

## 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)
- [DocuVision: PDF Q&A Without LangChain Plus a Vector DB](https://pixeltable.com/blog/docuvision-pdf-chart-qa)
- [Production RAG](https://pixeltable.com/use-cases/production-rag-implementation)
- [chat-with-pdf](https://pixeltable.com/tools/chat-with-pdf)
- [pdf-to-text](https://pixeltable.com/tools/pdf-to-text)