syntax prob

I am away from my server for the weekend and I need a little help.

when doing  updates of multiple fields there commas between 
the  elements?
I mean

update table set cname = 'Bill', caddress = '2nd floor' where acode = 
'AVAN';

I refer to the space between 'Bill' and caddress. 

if I could get to the server I would just try it. what happens if you have 
only 1 field to update and you add a comma, like this

update table set cname = 'Bill',  where acode = 'AVAN';

I am trying to concatenate an update string and I would love to not 
have to worry about the comma. I guess I could figure out how many 
things have changed then add commas... but I could also  wish for it 
to be easier.

Ted