17.10 - Null Sorts as the Lowest Value in a Collation - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - Database Design

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
User Guide
Publication ID
B035-1094-171K
Language
English (United States)

When rows are sorted using an ORDER BY clause, nulls sort as the lowest value.

If any row has a null in the column being grouped, then all rows having a null are placed into one group. In other words, though it is syntactically incorrect to formulate the predicate NULL = NULL in a DML request because nulls have no value and therefore cannot be equated, it is also true that when SQL sorts nulls, the implicit result is that NULL = NULL.