The following case applies to optimized uses of CASE partitioning expressions in a partitioning expression.
If you specify either a DATE, CURRENT_DATE, or a CURRENT_TIMESTAMP function in a partitioning expression CASE expression, then Teradata Database must scan and reconciles all of the rows in the specified table or join index when you update their values using an ALTER TABLE TO CURRENT statement.
Because of this, the best practice is not to specify DATE, CURRENT_DATE, or CURRENT_TIMESTAMP functions in the CASE expressions you specify in a partitioning expression.