17.10 - General - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - ANSI Temporal Table Support

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1186-171K
Language
English (United States)
  • The sys_start column must be defined as NOT NULL and GENERATED ALWAYS AS ROW START. The sys_end column must be defined as NOT NULL and GENERATED ALWAYS AS ROW END.
  • The GENERATED ALWAYS AS ROW START or END attributes cannot be dropped from the definitions of the columns that constitute the SYSTEM_TIME derived period column.
  • Component columns of a system-time derived period column cannot be part of the primary index.
  • To function as a temporal table, the system-time table must be defined WITH SYSTEM VERSIONING. (Valid-time tables do not have system versioning.)
  • A table can have only one system-time period definition.
  • A system-time table cannot be a queue, error, global temporary, global temporary trace, or volatile table.
  • CHECK constraints on tables with system time cannot include the start or end columns of the system-time period.
  • The start and end columns of the system-time period cannot be part of a primary or foreign key of a temporal referential constraint.
  • System-time tables cannot act as source tables in CREATE TABLE AS statements.
  • Statistics cannot be collected on the system-time derived period column, but they can be collected on the component start and end time columns.
  • Algorithmic compression (ALC) is not allowed on DateTime columns that act as the beginning and ending bound values of a temporal derived period column.