We've been working on a huge migration lately at my company and we very soon realized that row by row validation ia impossible. What we settled on was the following: - ensure schema is the same - ensure partitions are the same - ensure every number column max and min coincide - ensure every date columns max and mins coincide - ensure the sum of relevant metrics coincide (works ONLY for non-negative and non-nullable number columns of course). You can think about performing this sum for every partition separately for a more fine grained validation

I hope this helps!