excel changes your data to what it thinks is best, it does not 100% maintain actual values.
does your data have any FLOAT or REAL data types? since those are approximations, they might not be equal
Maybe you need to EXCEPT on a subset of columns, and not all columns?
I'm thinking that something like an identity column, or DWCreatedDate/DWUpdatedDate might be different, but the data is the same?
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