Important Salesforce Certified Platform Developer II (Plat-Dev-301) Exam Questions

Answer: B, C

Explanation:

Selective queries in SOQL are optimized for performance. Query B is selective because it filters out empty names, which are likely to be less in number. Query C is selective if the list of names is small, and 'Customer_Number_c' is indexed or can be used as an external ID field. Reference: Working with Very Large SOQL Queries

Answer: C

Explanation:

Making a callout from an Apex trigger is not allowed synchronously; hence, such callouts must be performed in an asynchronous context. The only way to perform this within the Salesforce platform is by using asynchronous Apex, such as @future methods or Queueable Apex.

Answer: D

Explanation:

Use AuraHandledException in try-catch for custom errors. It enables sending meaningful, user-friendly error messages to the Lightning component.

Answer: C

Explanation:

Application Events in Aura components are used for communication between components that are not in the same containment hierarchy. An application event to alert users about the arrival of a guest at the front desk is appropriate because it allows any component within the app to listen and respond to the event, regardless of where it is located in the component hierarchy.

Answer: C

Explanation:

Using Database.setSavepoint() and Database.rollback() within a try-catch statement is the recommended approach for handling transactions that involve multiple DML operations. This allows the developer to roll back all changes if an error occurs, ensuring that partial changes are not committed to the database.