This should do the trick:
Initial query check:
Code:
select m.[Name], p.XmlPackage, p.*
-- update p set p.XmlPackage = 'someXmlPackage.xml.config'
from Product p
inner join ProductManufacturer pm on pm.ProductId = p.ProductId
inner join Manufacturer m on m.ManufacturerId = pm.ManufacturerId
where m.[Name] = '{whichever manufacturer}'
You would then run the update statement to reflect the changes.
Code:
update p set p.XmlPackage = 'someXmlPackage.xml.config'
from Product p
inner join ProductManufacturer pm on pm.ProductId = p.ProductId
inner join Manufacturer m on m.ManufacturerId = pm.ManufacturerId
where m.[Name] = '{whichever manufacturer}'