---
title: "What is an AI function?"
description: "An AI function is a model call expressed in the schema — caption, transcribe, generate — rather than a separate pipeline product."
url: "https://pixeltable.com/learn/what-is-an-ai-function"
updated: "2026-09-29"
vertical: "Orchestration"
doc: "https://docs.pixeltable.com/datastore/computed-columns"
---

# What is an AI function?

An AI function is a model call expressed in the schema — caption, transcribe, generate — rather than a separate pipeline product.

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

## On this page

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

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


- The call is an expression on a column.
- Inputs are other columns.
- The output is stored and reusable.

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

It is not a chain of model calls with no stored outputs.

## AI function: this, and the thing it is confused with {#comparison}

|  | This | Not this |
| --- | --- | --- |
| Lives | On the row | In a notebook cell |
| Rerun | When inputs change | Every request |
| Output | A column | A response you forget to save |

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

Pixeltable AI functions are computed columns that call a model. The result is just a column.

## Questions {#questions}

### How does AI function work? {#faq-1}

The call is an expression on a column. Inputs are other columns. The output is stored and reusable.

### What is AI function often confused with? {#faq-2}

It is not a chain of model calls with no stored outputs.

## In the blog

- [Turn Any Database Table into an AI Tool: Introducing pxt.retrieval_udf()](https://pixeltable.com/blog/retrieval-udf-database-ai-tool)
- [AI Functions vs. Pipelines: The Pixeltable Declarative Approach](https://pixeltable.com/blog/ai-functions-vs-pipelines)
- [From Data Silos to Unified AI: The Three-Step Transformation Every AI Team Needs](https://pixeltable.com/blog/from-data-silos-to-unified-ai-three-step-transformation)
- [DeepSeek: Advanced Reasoning and Code Generation with DeepSeek-V3 in Pixeltable](https://pixeltable.com/blog/deepseek-reasoning-code-pixeltable)
- [Unleash Google's Multimodal AI Power with Pixeltable's Gemini Integration](https://pixeltable.com/blog/working-with-gemini)

## Related

- [Documentation](https://docs.pixeltable.com/datastore/computed-columns)
- [AI Functions vs. Pipelines: The Pixeltable Declarative Approach](https://pixeltable.com/blog/ai-functions-vs-pipelines)
- [AI Transformations Belong in the Schema, Not Bolted on Top](https://pixeltable.com/blog/ai-transformations-in-the-schema)
- [Declarative data infrastructure](https://pixeltable.com/use-cases/declarative-ai-data-infrastructure)