Hi Joycee,
This is a tough one! I can think of two approaches. The first is statistical. You can sample records and see if the data synced. Using statistics you can calculate how many records you need to sample to have a desired confidence that the records did in fact sync.
The second approach would be to look for merges in the activity log that were driven by the DT match rules. You could then check those records programmatically to ensure that they have a DT crosswalk.
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Gino Fortunato
Senior Solution Engineer
Reltio
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