Product resolution and unique counts

Listings have been matched to the product/s exactly. Group by product
and calculate the number of unique mega-pixel ratings on those listings.
Use the most common one as the product's resolution. Record the number
of different mega-pixel ratings for further investigation.
Export exact matches with conflicting resolutions

Export product+listing combinations to a csv file (for further analysis
and refinement) where there are multiple listing resolutions for the
same product