So I am hitting some resistance on a design. Basically, the DBAs don't like using the Xml datatype in the database tables. Instead, I've been told to create a table that stores Attribute Value pairs. Basically, we're storing either scaler or complex values into the Xml column, however, they all have the same Xml Schema. Now, I need to split the data from the Xml coming in and put it into multiple Rows in an EAV table. Don't get me wrong, I am a fan of EAV when it's needed, however, I don't think it's needed in this case.
My question is, what really is the performance impact of the Xml datatype? I mean ideally using the [TEXT_FILEGROUP] of the table I am able to store the Xml data into a seperate FILEGROUP and therefore even a seperate physical file on disk. I understand that space-wise it's probably a little larger, but if this one Xml column is never Indexed or used in any WHERE clauses, what is the performance impact of it?