Period Value Constructor Rules - Advanced SQL Engine - Teradata Database

The following rules apply to the Period value constructor:

• The beginning bound must have a DateTime data type and, if an ending bound is specified, the data types of the beginning and ending bounds must be comparable.
• The ending bound where the data type of the beginning bound is DATE or TIMESTAMP can be set to UNTIL_CHANGED.
• If the ending bound is set to UNTIL_CLOSED, the following must be true:
  • The data type of the beginning bound value must be comparable with TIMESTAMP(6) WITH TIME ZONE.
  • The constructor is only valid in an assignment operation where the target column to which the result is assigned is a transaction-time column.
  • Because the only way to set the value of a transaction-time column is by using nontemporal DML, the constructor is only valid in a nontemporal DML statement.
• The system reports an error if any of the following are true:
  • UNTIL_CHANGED is specified for the beginning bound.
  • The result beginning bound is greater than or equal to the result ending bound.
  • The data types of the beginning and ending bounds are not comparable.
  • UNTIL_CHANGED is specified for the ending bound and the data type of the beginning bound is TIME(n) [WITH TIME ZONE].
  • UNTIL_CLOSED is specified for the beginning bound.