SQL CASE

SQL CASE

The CASE statement goes through conditions and return a value when the first condition is met (like an IF-THEN-ELSE statement). So, once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the ELSE clause.

If there is no ELSE part and no conditions are true, it returns NULL.

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

 

Example:

SELECT OrderID, Quantity,
CASE WHEN Quantity > 30 THEN “The quantity is greater than 30”
WHEN Quantity = 30 THEN “The quantity is 30”
ELSE “The quantity is under 30”
END AS QuantityText
FROM OrderDetails;

mysql case example 1
mysql case example 1

 

MySQL example 2

 

mysql case example
mysql case example