This code snippet is illustrative of a common pattern in CRM - getting associated records. This is particularly useful for deals and line items where line items are inherently tied to a specific deal.
This particularly code snippet shows this in context of the following use case: A customer is looking to more easily quantify how many high value items are included on a deal. For every Closed Won deal, they would like to set a property value of the number of line items greater than $1,000 (Note: You can build a similar report like this in the custom report builder...but assume the customer wants to include the value as a deal property)
Robert, being very new to this, how hard would it be to basically sum up the Monthly Recurring Revenue line items (hs_mrr) and IF the amount = 0 then replace amount with the total of hs_mrr line items?