How Can I Use CASE Statements to Condense Conditional Logic in SQL SELECT Statements?

Exploring the CASE Statement in Select Statements

In SQL, the CASE statement allows us to conditionally evaluate expressions and return different results based on those conditions. When used within a SELECT statement, the CASE statement can replace multiple IF-THEN-ELSE statements, making the query more concise and easier to read.

Consider the following scenario: you have a table containing user data, including their names, ages, and preferred smartphone brands. You want to create a query that retrieves specific information while also categorizing the brands into different price ranges.

To achieve this, we can use the CASE statement as follows:

SELECT name, age,
CASE
  WHEN bbb THEN 'blackberry'
  WHEN sss THEN 'samsung'
END AS handphone
FROM (SELECT ... /* Your data retrieval query here */) AS Subquery;

In the example above, the CASE statement assigns the value 'blackberry' if the condition "bbb" is true and 'samsung' if the condition "sss" is true. The results would then be displayed in the 'handphone' column.

This approach allows us to dynamically determine the values based on specific conditions, making it a versatile tool for data manipulation and conditional processing in SQL queries.

The above is the detailed content of How Can I Use CASE Statements to Condense Conditional Logic in SQL SELECT Statements?. For more information, please follow other related articles on the PHP Chinese website!