17.05 - Using the NULL Option for SET SESSION CONSTRAINT - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Release Date
January 2021
Content Type
Programming Reference
Publication ID
B035-1144-175K
Language
English (United States)

The purpose of the NULL option for SET SESSION CONSTRAINT is similar to the NULL option for SET ROLE, where the request removes the active role for a session.

If the session is set to NULL for a constraint in place of one or more constraint names, the assigned constraint set must be currently assigned to the session. If you do not have the OVERRIDE privilege, Vantage returns an error. Constraint UDFs can accept a null from data rows, but not from a user session.