What is a flattened BOM?

"Think of a flattened BOM as a list of all the parts from all levels of your BOM listed together and the aggregate total quantities for each part are shown. It's a great way to see the quantities of ALL Parts (no matter what level of the BOM they appear) with their summed quantities." ( https://help.openbom.com/2018/09/08/bom-single-level-multi-level-flattened/ )

Let's say you have a product a0, consists of 3 sub-assemblies, b1, b2 and b3. And you stroe the single level bom of a0 as a0.csv .

a0.csv: child quantity
        b1           1
        b2           2
        b3           3

also, b1 and b2 has their own single bom, while b3 is a part at the bottom level.

b1.csv: child quantity
        c1           1
        c2           2

b2.csv: child quantity
        c1           2
        c2           4

c1 consists of d1 and d2, while c2 is on its own.

c1.csv: child quantity
        d1           4
        d2           8

In summary you have 4 csv files, or single-level boms, as input, this tool will give you one csv file, a flattened-bom, as output.

flattened.csv: parent child quantity
               a0     b3           3
               a0     c2          10
               a0     d1          20
               a0     d2          40
               b1     c2           2
               b1     d1           4
               b1     d2           8
               b2     c2           4
               b2     d1           8
               b2     d2          16
               c1     d1           4
               c1     d2           8

If you have a customer, internal or external, who would like a dashboard built on excel spreadsheet (what a supprise) to show and/ or estimate raw material usage, this could easily be integreted using Power Query.

In production (e.g. material usage calculation), you may also need to take other factors such as UoM into consideration.

I may reactivate the Matrix BoM repo at some stage.