16.20 - COALESCE Expression - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
16.20
Release Date
March 2019
Content Type
Programming Reference
Publication ID
B035-1145-162K
Language
English (United States)

Purpose

Returns NULL if all its arguments evaluate to null. Otherwise, it returns the value of the first non-null argument in the scalar_expression list.

COALESCE is a shorthand expression for the following full CASE expression:

   CASE 
    WHEN  scalar_expression_1  IS NOT NULL 
    THEN  scalar_expression_1  
    ...
    WHEN  scalar_expression_n  IS NOT NULL 
    THEN  scalar_expression_n  
    ELSE NULL 
   END

Syntax