Check out example codes for "sql case". It will help you in understanding the concepts better.

Code Example 1

CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    WHEN conditionN THEN resultN
    ELSE result
END

Code Example 2

CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    WHEN conditionN THEN resultN
    ELSE result
END;

Code Example 3

-- NOTE: this is for SQL-Oracle specifically

/*
NB: Please like Mingles444 post, I derived this from him/her
*/

-- syntax: (Retrieved from grepper:Mingles444)
CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    WHEN conditionN THEN resultN
    ELSE result
END 

-- example:
SELECT 
	CASE
      WHEN (1+6 = 6) THEN 'A'
      WHEN (1+6 = 7) THEN 'B'
      WHEN (1+6 = 8) THEN 'C'
      ELSE 'D'
	END 
FROM DUAL;

-- OUTPUT: B

Code Example 4

/*CASE statements are used to create different outputs and is 
  used by SQL as a way to handle if-then logic.*/
  
  SELECT column_name,
    CASE 
      WHEN condition THEN 'Result_1'
      WHEN condition THEN 'Result_2'
      ELSE 'Result_3'
    END
  FROM table_name;

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