---
title: "Configure User Defined Functions (UDFs) On TigerGraph Savanna"
component: "savanna"
version: "main"
module: "graph-development"
html_url: "/savanna/main/graph-development/advanced-features/configure-udf.html"
---

[View as HTML](/savanna/main/graph-development/advanced-features/configure-udf.html) · [Documentation index](/llms.txt)

# Configure User Defined Functions (UDFs) On TigerGraph Savanna

User-Defined Functions (UDFs) in TigerGraph allow you to incorporate custom logic into your GSQL queries. You can configure GSQL to your UDF definitions from a GitHub repository. This is TigerGraph's recommended approach for managing UDFs.

## Prerequisites

* Familiarity with GSQL and UDF syntax.
* An active TigerGraph Savanna workspace.

## Steps to Update a UDF

1) Set up the TigerGraph Savanna workspace and ensure it is running.

2) Edit the workspace by clicking the **…​** button of your selected workspace.

3) Navigate to the **Graph Admin** tab.

4) Select the **GSQL** section, then configure the following entries:

![config udf](../_images/config-udf.png) 

| Input | Description | Example |
| --- | --- | --- |
| GitHub URL For UDF | Optional parameter used for GitHub Enterprise | `<https://api.github.com>` |
| GitHub Repository For UDF | The user and repository where the files are held | `sample_user/repository` |
| Repository Branch For UDF | The branch to access | `main` |
| Repository Path For UDF | Path to the directory in the repository that has ExprFunctions.hpp and ExprUtil.hpp | `src/` |
| GitHub User Access Token For UDF | The credential used to access the repository | `anonymous` |

5) Click **Save** to apply the changes.

> [!NOTE]
> Update Graph Admin configurations may require restart of certain services, which may impact the running queries/loading jobs/schema changes. Apply changes with caution.

## Best Practices

* Version Control: Keep track of changes to your UDFs using a version control system.
* Testing: Thoroughly test UDFs in a development environment before deploying to production.
* Documentation: Document the purpose and usage of each UDF for future reference.

## Troubleshooting

* Syntax Errors: Double-check the syntax of your UDF code.
* Logic Errors: Ensure that the logic within the UDF is correct and handles all edge cases.