MySQL CASE WHEN Explained: Syntax & Usage

In MySQL, the CASE WHEN statement is a way to implement conditional logic in a query. It is similar to the switch statement in programming languages, allowing for different logic to be executed based on different conditions.

The general syntax of the CASE WHEN statement is as follows:

CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    ...
    ELSE default_result
END

Here, condition1, condition2, etc. are conditional expressions, and result1, result2, etc. are the results returned when the conditions are met. The default_result is the result returned when no conditions are met.

CASE WHEN statements can be nested and combined with other functions and expressions to achieve more complex logic. By using CASE WHEN statements, different results can be dynamically returned based on different conditions, allowing for more flexible querying and data processing.