16.20 - DISTINCT Option - 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)

The DISTINCT option specifies that duplicate values are not to be used when an expression is processed.

The following SELECT returns the number of unique job titles in a table.

   SELECT COUNT(DISTINCT JobTitle) FROM Employee;

A query can have multiple aggregate functions that use DISTINCT with the same expression, as shown by the following example.

   SELECT SUM(DISTINCT x), AVG(DISTINCT x) FROM XTable;

A query can also have multiple aggregate functions that use DISTINCT with different expressions, for example:

   SELECT SUM(DISTINCT x), SUM(DISTINCT y) FROM XYTable;