Which option about non-SELECT queries is correct?

The option stating that it is mandatory to set the Output Entity or Structure in non-SELECT queries is correct because, in OutSystems, non-SELECT queries such as INSERT, UPDATE, or DELETE often require an output to ensure proper handling and tracking of the changes made in the database. Setting an Output Entity or Structure allows developers to understand the results of the operation being performed, including any affected records, which is crucial for managing data integrity and conducting further operations.

In many cases, especially for INSERT operations, this ensures that the application can obtain relevant information about the newly created record, such as its ID or related attributes, which might be needed immediately after the operation. Ensuring an Output Entity or Structure provides a means to confirm the success of the operation and allows for immediate feedback to the user or subsequent logic in the application to process the result correctly. This ties into broader concepts of data management and application logic within OutSystems, highlighting the importance of structured data handling during such operations.