update child records from flow multiple times

Question

Anyone has had the requirement of updating same child records from a flow multiple times, pertaining to multiple decisions, which may or may not be mutually exclusive?

Ideally I would wish to

1. assign whatever values they (child records) need if they satisfy decision 1
2. assign whatever values they need if they satisfy decision 2 etc.
3. have a single update element to update all of them

just like we do for parent (triggering) record - multiple assignment operators + one single update

But I seem to not be able to do that for child records. With the standard "Update records related to the (triggering object name) record that triggered the flow" - this is not possible to my understanding.

I am ending up with multiple updates on child records but can not think of a better way to do that. Would the following design be a better approach? We are moving out of the standard flow features by this way.

1. querying child records into a variable
2. running a loop with each decision (decision 1, decision 2 etc.) and assigning them accordingly
3. one collection update of this child records list

Answer 1

Basically, I agree with your approach as that is how I would do this. Flow Interviews are only bulkified when they reach a common element. But your premise is that there would not be a common element.

Hence,

• use a record collection variable to cache the updates to the child records as you progress through your flow's business logic.
• when all business logic is completed, then do an Update Records element with input being the record collection variable. This will be bulkified across Flow Interviews of the same transaction.