List operations

Question 1

You have a list of users.
You want to change the age attribute of each user.
What’s the best practice to achieve this according to Mendix?

1. Loop
2. Change Object
3. Aggregate Object

Answer 1

1. Loop

Question 2

What elements does an optimized query consist of?

Answer 2

A Retrieve activity and a count activity.

Question 3

When are batches used?

Answer 3

Batches are used when large amounts of data need to be processed.

Question 4

What are loops used for?

Answer 4

Loops are used to iterate over a list of objects. For every object in a list, the flow inside the loop is executed.

Question 5

Which elements can’t be used inside a loop?

Answer 5

Start event and Stop events

Question 6

Which events can only be used inside of a loop?

Answer 6

Break event and Continue event.

Question 7

What is a Continue event used for?

Answer 7

A Continue event is used to stop the current iteration and start the iteration of the next object inside a loop.

Question 8

What is a Break event used for?

Answer 8

A break event is used to stop iterating over the list of objects and continue with the rest of the flow.