17.10 - For ALL - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - 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)

Two nested NOT EXISTS can be used to express a SELECT statement that embodies the notion of “for all (logical ∀) the values in a column, there exists (logical ∃) …”

For example the query to select a ‘true’ value if the library has at least one book for all the publishers can be expressed as follows:

   SELECT 'TRUE' 
   WHERE NOT EXISTS
    (SELECT * 
     FROM publisher pb 
     WHERE NOT EXISTS
      (SELECT * 
       FROM book bk 
       WHERE pb.PubNum=bk.PubNum);