# User-Defined Functions in T-SQL

User-Defined Functions in T-SQL: User-Defined Functions in T-SQL.

Updated: November 3, 2026

1. [User-Defined Functions in T-SQL](https://www.ask-codey.com/lessons/user-defined-functions-in-t-sql) (Journeyman): Write your own functions. A scalar function returns one value and works inside any query; a table-valued function returns rows and works like a table that takes parameters.

Source: https://www.ask-codey.com/courses/csharp-full-stack-bootcamp/topics/user-defined-functions-in-t-sql