17.10 - Derived Period Columns and SELECT - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Temporal Table Support

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1182-171K
Language
English (United States)
In addition to the regular rules for use of derived period columns with SELECT described in Teradata Vantage™ - SQL Data Manipulation Language, B035-1146, the following rules and restrictions apply to the use of derived VALIDTIME and TRANSACTIONTIME columns in temporal tables.
  • Component columns of derived VALIDTIME and TRANSACTIONTIME columns are not projected for CURRENT and SEQUENCED SELECT * requests.
  • Component columns of derived VALIDTIME and TRANSACTIONTIME columns are projected for NONSEQUENCED SELECT * requests.
  • The system generated VALIDTIME column that is projected for a SEQUENCED VALIDTIME query will be a true period data type column, even if the valid-time column of the queried table is a derived period column.