How to find if matching value exists in another column of a dynamically filtered dataset

[danielcarpenter]

In plain english what I am trying to do is....

1. Given a dynamically filtered dataset
2. Take the parent id value for each row and search for a matching value in the issue id column of the filtered result set
3. If the value is present in the filtered dataset then count the row; if not then do not count the row

Here is some sample data demonstrating the desired result and rationale

And here is what I've created for DAX so far, but it is only identifing the parents rows and not identifying the child rows whose parent is in the filtered dataset.

parent in dataset = 
var parentlink = 
    IF(HASONEVALUE(table[parent_id]),MAX(table[parent_id]),"")
return
    COUNTX(
        FILTER(table,
        CONTAINS(ALLSELECTED(table),table[issue_id],parentlink)
        ),table[issue_id]
    )

Thanks in advance for your assistance!

[danielcarpenter · Accepted solution]

I figured out this problem and sharing here

parent in dataset = 
//define epics as the basis for evaluation
var parent = VALUES(table[parent_id])

//defines logic for evaluating if epic is owned or not
var matches = 
    IF(
        CALCULATE(
            COUNTROWS(table),
            ALLSELECTED(),
            TREATAS(parent,table[issue_id])
        ),1,BLANK()
    )

return
//perform logic for each row in table
SUMX(table,matches)

[BenCratsley]

Can this be implemented as a measure? or only a calculated column?

[danielcarpenter]

The above formula is a measure. This use case cannot work as a calculated column as the dataset is filtered dynamically based on user filter selections. 

[lbendlin]

your ID-1525 row actually points to another scenario that you have not considered in your formula approach.

1. parent present and child(ren) present

2. child(ren) present but parent not present

3. parent present but no child(ren) present

You need to compute each scenario separately.

[danielcarpenter]

Rows like issue ID = ID-1525 (the parent rows) are the only rows working with my current formula. I haven't found an approach that identifies the children - navigating the row context to find matching values in different rows appears to be my challenge.