Exam PL-400 topic 1 question 28 discussion

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/register-plug-in#define-entity-images

To access the record columns before the operation starts and compare them to post-update values, you should: B. Register a pre-image by using the Plug-in Registration Tool. Add the code to the plug-in to read the image from the PreEntityImages collection. Registering a pre-image allows you to capture the state of the record before the update operation. This way, you can compare the pre-update values (from the pre-image) with the post-update values (available in the InputParameters collection) within your plug-in logic1.

A pre-image is a snapshot of the entity's data before the update operation occurs. By registering a pre-image, the plug-in can access the values of the entity's columns before the update. This allows for comparison with the post-update values in the Target entity. This is the correct approach to accessing pre-update values.

B. For comparison use Pre-image and for showing updated record use post-image here in question they said must compare so it should be pre-image.

Using a pre-image alone would not fulfill the requirement, as it only provides the state before the update, not after. With a post-image, you capture the state of the entity after the operation has occurred, which includes the updated values of the record's columns. This allows us to compare the columns before and after the update, fulfilling the requirement of the scenario.

B is correct

The plug-in logic requires access to the record columns before the operation starts and must compare the columns to post-update values. see the question -if postEntityImage contains both images before and after update then C is the answer

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/register-plug-in#define-entity-images "If your plug-in step is registered in the PreValidation or PreOperation stages of the execution pipeline, you could use the IOrganizationService instance to retrieve the current value of the property, but this isn't a good practice for performance. A better practice is to define a pre-entity image with your plug-in step registration. This will capture a 'snapshot' of the table with the fields you're interested in as they existed before the operation that you can use to compare with the changed values."

Chatgpt Answer is also B

ANSWER IS B

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/register-plug-in#define-entity-images For an Update operation that is registered in the PostOperation stage you can have both a Pre Image AND a Post Image. So the answer seems Correct.

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/register-plug-in#define-entity-images

Correction I meant b

Pre entitiy images have the value before the update. Then you can compare the values before and after the update happened