FreeTDS Development Group

["Lowden, James K" <LowdenJK AT bernstein.com>]

> From: Vadym Kononenko
> Sent: Thursday, August 18, 2005 8:30 AM
> 
> On Thursday 18 August 2005 14:44, Thompson, Bill D (London) wrote:
> > If at all possible, I would build your libdbi api on top of one
> > of the existing api's - dblib ctlib or odbc.
> 
> I can imagine the way to make FreeTDS dbd driver for DBI using
> ctlib or dblib, but it's incorrect to do the driver using odbc
> anyway, because DBI architecture is too similar to ODBC.  So may
> be You right, but I'm not sure which one of dblib or ctlib is better
> to use for my task? Can You (or anyone else) help me?

Hi Vadym, 

libdbi looks like an interesting project.  You'll find lots of support
here.  

I second Bill's suggestion to use the ct-lib API.  It's throughly
documented on Sybase's site, and it's used by DBD::Sybase (and has been,
for years).  There are some things that DBD::Sybase can do with Sybase's
drivers that FreeTDS doesn't yet support, but the basic DBI
functionality has been in place for several years.  By adopting ct-lib,
I would expect you'll find patterns in DBD::Sybase that you'll want to
follow, and compatibility testing should be easier.  Also, if you (or
Michael Peppler) encounters a bug in the FreeTDS ct-lib implementation,
both libraries will benefit from the fix.  

Several attempts were made in the past by other projects to use libtds
directly.  AFAIK, they all failed -- were abandoned and became obsolete
-- for exactly the reasons Bill outlined.  Unless you want to become a
FreeTDS developer, you're much better off using a published and public
API.  

For example, I'm just now in the process of changing how error handling
works.  The change affects how libtds communicates errors to the client
libraries and how they return status information.  If you finish before
I do (quite possible) a libtds-based libdbi would be obsolete with the
next release of FreeTDS.  

Have fun with it, and give a shout if you need help.  

Regards, 

--jkl

-----------------------------------------
The information contained in this transmission may be privileged and
confidential and is intended only for the use of the person(s) named
above. If you are not the intended recipient, or an employee or agent 
responsible
for delivering this message to the intended recipient, any review, 
dissemination,
distribution or duplication of this communication is strictly prohibited. If 
you are
not the intended recipient, please contact the sender immediately by reply 
e-mail
and destroy all copies of the original message. Please note that we do not 
accept
account orders and/or instructions by e-mail, and therefore will not be 
responsible
for carrying out such orders and/or instructions.  If you, as the intended 
recipient
of this message, the purpose of which is to inform and update our clients, 
prospects
and consultants of developments relating to our services and products, would 
not
like to receive further e-mail correspondence from the sender, please "reply" 
to the
sender indicating your wishes.  In the U.S.: 1345 Avenue of the Americas, New 
York,
NY 10105.