CSV – Processing all the rows with same value at once [closed]

I have a large CSV file with the following headers “sku”,”year”,”color”,”price”,”discount”,”inventory”,”published_on”,”rate”,”demographic”,”tags” and I’d like to be able to process once at the time all the rows having the same “sku”,”year”,”color” without loading all the file at the beginning or creating a huge data structure (array/hash) containing all the rows. I’m trying to create a loop…

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