I can't check it at this moment, but I don't think any recent MS SQL (that is 7.0 and up) does this for varchars. I'm sure I would notice. It does change an empty string to a string containing the right number of spaces for char(N) columns, but there it can't do anything better. If I still remember this node tomorrow when I am at work and can try things I'll test it and post an update.

Update: Yep, I was right:

create table foo (svarchar varchar(10), schar char(10))

insert into foo (svarchar, schar) values ('', '')
insert into foo (schar) values ('')

select '>' + svarchar + '<', '>' + schar + '<'
from foo
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