SQL UDFs in Iceberg

[sxlin]

Proposed Change

A user-defined function (UDF) is a callable routine that accepts input parameters, executes the function body, and returns either a single scalar value or a table based on the UDF type.

Most compute engines (e.g. Dremio, Snowflake, Trino and Apache Spark) support UDFs . Without a common standard, the UDFs are hard to share among different engines. It allows versioning of UDFs if they are stored in Iceberg. This proposal standardizes the UDF metadata.

Proposal document

https://docs.google.com/document/d/1BDvOfhrH0ZQiQv9eLBqeAu8k8Vjfmeql9VzIiW1F0vc/edit?usp=sharing

Specifications

• Table
• View
• REST
• Puffin
• Encryption
• Other

[github-actions]

This issue has been automatically marked as stale because it has been open for 180 days with no activity. It will be closed in next 14 days if no further activity occurs. To permanently prevent this issue from being considered stale, add the label 'not-stale', but commenting on the issue is preferred when possible.

[ajantha-bhat]

Will get back to this. Not stale.