Reduce duplicate Rows in Reports: Aggregate/merge related data in a cell (in a pivot report or hierarchy report)

Overview - Reports contain multiple rows with instances of the Primary Record Type as soon as you add a column from a "Related Object" that has multiple values, making it hard to visually consume the data.

Problem - In List Reports we see the value of each Primary Record Type repeated in multiple rows for any record that has more than one value in a many-to-one relationship. This creates output with unnecessary duplication that makes the report difficult to read.

Root Cause (with example)

1. Each Initiative can have multiple Goals linked
2. A List Report (Features -> List) generates one report row for each Goal linked to an Initiative
3. This is because there are no aggregation rules that would allow every Goal linked to this Initiative within the single Initiative row

Desired Outcome (in context of Root Cause example)

1. Show one row per Initiative, with "n" comma-separated values in the Goals column (where "n" is equal to the number of Goals linked to that Initiative)

Possible Solution

1. Create a UI feature on Pivot (and Heirarchy?) reports that allows a "non-Primary Record Type" Column to aggregate and comma separate values where not aggregating these values would otherwise result in producing duplicate rows of the Primary Record Type

Steps to replicate

1. Create 3 new Goals
2. Create 3 new Initiatives
3. Relate all three Goals to each of the 3 Initiatives (total 9 "relationships")
4. Create a "Feature List" (aka custom pivot) https://example.aha.io/products/ABC/bookmarks/feature_grids/new
   1. Set "Primary Record Type" to "Initiative"
   2. Using "Add records related to Initiative" choose "Goal"
5. Instead of seeing 3 rows (One Goal per Initiative, 3 values per row in the Goal column) you see 9 rows (Each Initiative 3 times, once for each Goal on each Initiative).