Having problems figuring this out:

This gives an error, complaining about the Order by clause. Must be caused by the nvl() function?

Select vendor From CopyTemplateMtl
 Union All
  Select Nvl(vendor,'') From c:\testdata
   Order By vendor

I also tried:

Select vendor From CopyTemplateMtl
 Union All
  Select Nvl(vendor,'') as vendor From c:\testdata
   Order By vendor

If I leave out the Order By clause, it works, but the results are not ordered like I want.