If (2 different dimensions with the same data) occur, then 1, else 0

I'm trying to figure out how to count whether or not something occurs on the same day... or perhaps occurs at all.

I have 2 dimensions:  [TRACE ID] and [PROD ID]

Both are the exact same #.  However, the [PROD ID] only shows up if a defect has been written against it.

Situation:

We audit about 1/2 of the parts we send into assembly.  Each audit has a "traceable #" we input into it's own column called  [TRACE ID]

- This audit is logged as an event telling us we audited the part.

After we audit the part, component, product, etc it goes into assembly, and we log defects.

We write up defects all day... and when writing up a defect we input the "traceable #" into an entirely different column called [PROD ID]

-This defect log creates an entirely new event.

The question my VIZ needs to answer:  Of the Parts we Audited, how many had defects wrote up against them?

I am having a hard time wrapping my head around the solution:

Something like:

IF [TRACE ID] is found in the [PROD ID] column then = Defect Found

else null

end

Any ideas on how to write this up?