MDAC and SQL Server 2005

In the SQL Server 2005 upgrade advisor help file it states the following...

"Upgrade Advisor detected an older version of MDAC. MDAC versions before MDAC 2.8 SP1 do not support named instances. To allow application connections to named instances, upgrade to MDAC 2.8 SP1."

I've installed our application which uses ADO (not ADO.NET) to connect to an SQL Server named instance on a client machine. Our application installs MDAC 2.6. Therefore on older machines such as Windows 95 MDAC is upgraded to 2.6. Our application can still connect to the named instance without MDAC 2.8 SP1 being present.

Is this statement in the upgrade advisor entirely true or am I misunderstanding what it means?

Thanks.MDAC 2.6 does support named instances. However, SQL Server 2005 requires MDAC 2.8SP1 or higher

Hope this helps.

Regards
Uwa|||Thanks for the reply. When you say SQL Server 2005 requires MDAC 2.8SP1 or higher, do you mean being able to use SQL Server itself on the machine it is installed on or do you mean 2.8SP1 is required by clients for connectivity.

I've got a client machine here with MDAC 2.6SP2 installed where our application can perfectly connect to my server which is running SQL Server 2005 in a named instance.

Thanks|||SQL Server 2005 requires MDAC 28SP1 or higher on the machine it's installed on. Client machines with any MDAC version can connect to it but with some possible limitations (for example there is no support for named instances prior to MDAC 26).

For better performance and if you use the new data types in SQL Server 2005 or other cool new features (MARS, notifications etc), I would recommend you use the new SQLNCLI (SQL Server native client) which has the equivalent of the OLEDB provider and ODBC Driver in one DLL package. It has it's own MSI installer that is on the Server media. Please see http://support.microsoft.com/?kbid=910016 for more info|||Thanks for the information. My main concern is getting our existing applications that are based on SQL Server 2000 working with SQL Server 2005 so I am just concerned about MDAC at the moment.

I will certainly check out SQLNCLI though as that sounds interesting.

Thanks|||SQL Native Client is a good choice if you are using new features in SQL Server 2005. It's peformance is likely to be better than MDAC in many cases and it also scales better on multiprocessor machines.

However, if you have deployed clients and you are simply upgrading the server to SQL Server 2005 there is no requirement to upgrade from MDAC to SQL Native Client.|||

Thanks guys for good info.

I have a similar question. We have an application (C++ and built in 32bit) using ODBC driver to connec to SQL Server 2000 or Oracle 9 server. Can our application connect to SQL Server 2005 (64bit) without modification? We dont mind to install MDAC 2.8SP1 on the SQL Server 2005 (64bit) machine.

I would appreciate your help.

John

|||

ODBC connectivity to SQL Server 2005 on 64bit is supported either via MDAC or the new SQL Native Client ODBC driver (which offers better performance and features in some areas).

And by the way, MDAC 28 is part of the Windows 2003 and XP operating systems so you will not need to install this.

Hope this helps.

Uwa