[freetds] problems storing more than 8000 bytes of data in a varchar(max) column
Bob Hetzel
beh at case.edu
Fri Aug 17 13:46:18 EDT 2007
There's actually a big plus side to the varchar(max) field type however.
It also gets around a limitation in record size. Previously, changing
to text fields was required so your record wouldn't go past a page
limit, not as well as to allow 1 big field in a record. However, that
had limitations on how you could search. The varchar(max) field type
removes those limitations. Too bad they didn't just figure out a way to
extend the varchar datatype seamlessly, but I guess db engine designers
like to help keep dba's employed. :)
Bob
James K. Lowden wrote:
> Moritz Bunkus wrote:
>> But the MS
>> SQL Server 2005 documentation states in various places that "text" type
>> columns are deprecated and will be removed in future versions. It
>> suggests using the column type "varchar(max)"
>
> Ah, I see. I hadn't come across that yet, thanks.
>
> FWIW, I wouldn't worry too much about deprecation announcements. There
> are a lot of databases and software out there that use TEXT. It will take
> years to do away with it.
>
> I guess it was 10 years ago Microsoft deprecated db-lib. First they
> warned us about it, then they stopped updating it, then they stopped
> including it, then they dropped the documentation. But it still works.
> We've also been told for years not to use the system tables, to rely
> instead on the information schema views. Except the only place some
> things can be found is in the system tables and -- wouldn't you know it?
> -- that's what Microsoft's own procedures use.
>
> Also, sometimes the advice about the future changes before the future
> arrives. There've been some dead ends. Don't get me started about
> SQL-DMO. And then there are the unwarned-about changes, like substituting
> 'sys' for 'dbo' and changing the optimizer in ways that made some
> pre-existing queries run slow. However hard you work to prevent problems
> with future releases, there will always be some.
>
> My policy is to use what I know and take advantage of new features when
> they're helpful. If and when the day comes that Microsoft says not "in
> future versions" but "in the next version", you'll know it's time to the
> big search-and-replace.
>
> BTW, if you do use DBD::Sybase, be advised placeholders don't work. They
> can't, because of the way they're defined in ct-lib.
>
> Regards,
>
> --jkl
> _______________________________________________
> FreeTDS mailing list
> FreeTDS at lists.ibiblio.org
> http://lists.ibiblio.org/mailman/listinfo/freetds
More information about the FreeTDS
mailing list