Certified Pega System Architect v7.2 — Question 16

You have created a series of forms for a vacation booking process. Declarative expressions are used to calculate values such as the cost of the flight, hotel, car rental, and taxes. The last form includes a field that displays the total amount that will be charged on the users credit card.
How do you configure the calculations so that the total amount is calculated only when the user reaches the last form?

Answer options

• A. Use the backward chaining option for all the expressions.
• B. Use the backward chaining option for the total amount expression. Use forward chaining for all the other expressions.
• C. Use the forward chaining option for all the expressions.
• D. Use the forward chaining option for the total amount expression. Use backward chaining for all the other expressions.

Correct answer: C

Explanation

The correct answer is C because using forward chaining for all expressions allows the calculations to happen as soon as the user provides input, which is necessary for real-time updates. Options A and B incorrectly suggest using backward chaining, which would not allow for immediate updates. Option D also incorrectly suggests using backward chaining for other expressions, which is not suitable for this scenario.