@Will Needham Your notes says regarding the function "Only SELECT statements, can never edit the underlying data (using UPDATE/ INSERT etc)" where as when I see the MS documentation it says "In Transact-SQL data manipulation statements (DML) such as UPDATE, INSERT, and DELETE" , Please clarify https://learn.microsoft.com/en-us/sql/t-sql/statements/create-function-sql-data-warehouse?view=fabric&preserve-view=true