Concatenate rows values based on DAX MEASURE value

[Anonymous]

I am trying to concatenate the [Step] column and also sum the [Quantity] column if the cumulative total is < required balance AND also the first instance where the cumulative total is >= required balance

What I am trying to do is to find out for each specific product, are the ones which has progressed the furthest (highest [Step]) along the chain, and seek them out to meet my [Required balance].

The pain comes because [Product], [Step], [Quantity], [Required balance] is part of an actual column, while [Cumulative total] and [Cumulative total < Required balance] is a calculated measure. 

2 tables are involved here:
Required balance: [Product], [Required balance]
Quantity: [Product], [Step], [Quantity]

'Required balance'[Product] is linked to 'Quantity'[Product] in a one-to-many relationship.

Product	Step	Quantity	Required balance	Cumulative total	Cumulative total < Required balance
A	10	12	75	12	True
A	9	71	75	83	False
A	8	12	75	95	False
A	7	48	75	143	False

Ideally my output should be:

Product	Steps required	Cumulative total
A	10, 9	83

@Greg_Deckler @amitchandak 

[MFelix · Accepted solution]

Hi @Anonymous 

Create the following measures:

Quantity Value = sum(Quantity[Quantity])

Steps Below =
VAR QuantityCumulative =
    ADDCOLUMNS (
        ALLSELECTED ( Quantity[Step] ),
        "@Quantity", [Quantity Value],
        "@CumulativeQuantity", [CUMULATIVE TOTAL]
    )
VAR QuantityBelowRequired =
    COUNTROWS (
        FILTER (
            QuantityCumulative,
            [@CumulativeQuantity] < SUM ( 'Required Balance'[Required balance] )
        )
    ) + 1
RETURN
    CONCATENATEX (
        TOPN ( QuantityBelowRequired, QuantityCumulative, [@CumulativeQuantity], ASC ),
        Quantity[Step],
        ",",
        Quantity[Step], DESC
    )


Cumulative value = 
VAR QuantityCumulative =
    ADDCOLUMNS (
        ALLSELECTED ( Quantity[Step] ),
        "@Quantity", [Quantity Value],
        "@CumulativeQuantity", [CUMULATIVE TOTAL]
    )
VAR QuantityBelowRequired =
    COUNTROWS (
        FILTER (
            QuantityCumulative,
            [@CumulativeQuantity] < SUM ( 'Required Balance'[Required balance] )
        )
    ) + 1
RETURN
    MAXX (
        TOPN ( QuantityBelowRequired, QuantityCumulative, [@CumulativeQuantity], ASC ),
        [@CumulativeQuantity]
    )

Final result below and in attach PBIX file.

[Anonymous]

This is such a clean measure (as compared to the one I came up with), perfect thanks!