The difference is that raw data can come in many shapes (e.g. impossibly nested jsons) and unexpected quality (changing field names...). I cannot easily work wi

The difference is that raw data can come in many shapes (e.g. impossibly nested jsons) and unexpected quality (changing field names...). I cannot easily work with this in SQL and definitely not write tests to cover the ever increasing complexity of dealing with messy data. After that step the data is a lot more uniform, so then it's easy to use SQL.