Question

What does the CASE WHEN THEN clause do?

1) It creates a new table named countries_plus
2) It creates a new column named countries_plus
3) It creates a new row named countries_plus
4) It creates a new database named countries_plus

Answer 1

The CASE WHEN THEN clause in SQL is a conditional statement used to create a new column in the result set of a query, where each value is based on defined conditions, not for creating tables, rows, or databases.

Step-by-step explanation:

The CASE WHEN THEN clause is a part of SQL (Structured Query Language) used in database management and querying. It is a conditional statement that provides a way to perform different actions based on different conditions. Essentially, it functions similarly to an if-else statement in programming. When a specified condition is met (WHEN), the statement will return a specific result (THEN).

In the context of the options provided in the question, the CASE WHEN THEN clause does not create tables, rows, or databases. Instead, it is used within a query to create a new column in the result set, where each row's value in that column is determined based on the conditions set in the CASE statement. Therefore, the correct option would be:

2) It creates a new column named countries_plus