17.10 - Triggers and Identity Columns - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Detailed Topics

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1184-171K
Language
English (United States)
The following rules and restrictions apply to triggers and INSERT operations into tables with identity columns.
  • You cannot create a trigger definition if its triggering statement is an INSERT on a subject table that has an identity column and its triggered action statement or WHEN condition references that column.
  • If a triggered statement makes row references to the table that is involved in the triggering statement, and the triggered statement is an INSERT operation into a table with a GENERATED ALWAYS identity column, Vantage substitutes a dummy value for the USING value for the referenced row and then generates the actual identity column number in the Dispatcher before sending it to its destination AMP.