16.20 - Examples of Character and Numeric Data in a CASE Expression: Example 1 - Advanced SQL Engine - Teradata Database

In the following query, the CASE expression returns a VARCHAR result because the THEN  and  ELSE clause contains FLOAT and VARCHAR values. The length of the result is 30 since the default format for FLOAT is a string less than 30 characters, and USER is defined as VARCHAR(30) CHARACTER SET UNICODE. The result is CHARACTER SET UNICODE because USER is UNICODE.

   SELECT a, CASE
                WHEN a=1 
                THEN TIME
                ELSE USER
               END
   FROM table_1
   ORDER BY 1;