Subject Information on serious issues with different ODBC drivers
Author mgastde <michael.gast@web.de>
Hi,

I've examined different serious problems with different ODBC drivers
available for Firebird.

Environment on the server:
Suse Linux 7.1
Firebird 1.00 and 1.02

Environment on the client:
Windows NT 4.0 SP5 or SP6 or Windows 2000 SP 2 or Windows XP
gds32.dll as delivered with the respective Firebird package for
Windows.

1. Easysoft ODBC driver:
Easysoft ODBC driver in different versions with and without support
for unicode. I've tested version 1.1.63 and the most recent versions
of the driver downloaded two weeks ago.
This driver has the following issue:
After rolling back a transaction with a select operation in it, the
counter for the OIT does not rise any more. A few weeks later, the
database starts to slow down and to produce irregular error messages.
The difference between OIT and the actual transaction number (OT) is
in this point of time roundabout 700000 (sweep is disabled due to
problems with a corrupted database when the server shuts down while
the sweep runs).
I've reported the error to Easysoft and they could confirm this error
running the driver against a Firebird database (and using a small test
database i've created). They state that the error does not occur with
the open source version of Interbase. I've not checked this.
But unfortunately Easysoft adds:
1. We are the only customer with this problem.
2. They classify this issue as a minor bug and they probably (!) will
fix it in one of the future releases.
That don't help us, as we use Firebird in a productive environment and
me must find a solution in the near future.

2. XTG ODBC driver:
This driver has exactly the same issue as the Easysoft driver.

3. IB-Phoenix open source ODBC driver:
This driver does not have the issue I've noticed with the Easysoft or
the XTG drivers. But I did not find a possibility to set the correct
character set. In addition, i cannot update or insert any data in my
test database (i did not check delete) using AQUERYX from XTG as
frontend and one of the snapshots builds as ODBC driver. Using the
release version of Juli 2001 i can modify my data, but i cannot set
the proper character set. So this driver actually is not usefull for
our german environment.

4. Gemini ODBC driver for Interbase and Firebird:
This driver does not have the described issue and it works fine with
different character sets. After doing a lot of testing, it seems for
me, that the Gemini ODBC driver is the only one working correctly. But
the last build available is version 2.1 dated to January 2001 and it
is not approved to work with Firebird 1.0.0 and Firebird 1.0.2.

There are still some questions:
* Are we really the only one with this problem?
* Does anyone use the Gemini driver in a productive environment? Are
there any problems?
* Is it planned to add character set support to the open source
driver?
* Does anyone else have the problem with writing operations using the
open source driver?

Best regards
Michael Gast