17.10 - Usage Notes - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1145-171K
Language
English (United States)

FIRST_VALUE and LAST_VALUE are especially valuable because they are often used as the baselines in calculations. For instance, with a partition holding sales data ordered by day, you may want to know how much the sales for each day were compared to the first sales day (FIRST_VALUE) for the period, or you may want to know, for a set of rows in increasing sales order, what the percentage size of each sale in the region was compared to the largest sale (LAST_VALUE) in the region.

IGNORE NULLS is particularly useful in populating an inventory table properly.

Selecting neither IGNORE NULLS or RESPECT NULLS is equivalent to selecting RESPECT NULLS.