How to write best CASE example in Teradata SQL

Teradata SQL
Teradata Case Statement
What is CASE statement?
  • CASE will provide logical control of the SQL. In CASE statement we can give >,<,=,<>
  • The CASE has structure it starts with CASE and end with END


 See an example of Advanced CASE:

 SELECT
  COMPANY,
  CASE
    WHEN DEPT_NO = 1 THEN 'HR'
    WHEN DEPT_NO = 2 THEN 'IT'
    WHEN DEPT_NO = 3 THEN 'FINANCE'
    ELSE 'I DON''T KNOW'
  END AS DEPT_NAME
FROM SAMPLES.COMP_DETL
ORDER BY 1;

 The above query covered all like ELSE, THEN, WHEN, CASE and END. This is the best example how typically,you can write CASE in an SQL query for logical validation.

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