[web2py] orderby first, then limitby

[pbreit]

I have a query that includes both orderby and limitby. What seems to happen 
is that the db returns some set of records as dictated by the limit and then 
orders the records in that set. So I pretty much get the same set every time 
even though I know the field being ordered has changed for various records. 
Is this how SQL works? Is there any way to order the whole set first and 
then return the sub-set?