FreeTDS Development Group

["James K. Lowden" <jklowden AT freetds.org>]

ZIGLIO, Frediano, VF-IT wrote:
> > Of course we'll need to add XSYBVARCHARMAX or something like that.  
> > 
> 
> This is the problem, there is no XSYBVARCHARMAX but XSYBVARCHAR is 2
> byte long for varchar(N) where N <= 8000 while is "chunked" when
> column_size is -1...

I need to understand this very clearly to be useful to you.  I've never
seen the data stream.  What does it look like?  How is it chunked?  

> So is_blob_type does not work. I agree that varchar(max) is a LOB but
> has no textptr/timestamp so use TDSBLOB structure waste some space and
> confuse programs.

My idea is to synthesize a textptr in libtds to make varchar(max) look
like TEXT to the client libraries.  I'm not worried about wasting a few
bytes, especially because -- if we're lucky -- the client libraries won't
have to change.  

Maybe I should work from the outside in.  How does ODBC (or native client)
handle varchar(max)?  Are you concerned that by converting varchar(max) to
TEXT, client programs will not get the datatype they expect?  

Regards, 

--jkl