Late Binding required with ADO objects? 1

[dabruins]

I'm developing a access db frontend to connect to a mysql database server. The access users may not have the same version of access or the same version of windows. When creating ADO recordsets, connections, and command objects is it necessary to use late binding techniques when declaring the variables so that compatibility is ensured for various users. I haven't seen many examples of ADO object declarations in code examples on this site ot others that use this technique so I'm wondering if it's an issue at all.

Thanks.

 

[Golom]

Late binding may get you around things like different MDAC releases on different machines but that raises another issue. If you did your development using MDAC 8.0 (for example) then late binding on a machine running MDAC 5.0 may get the object created but it won't necessarily run properly because MDAC 5.0 didn't support everything that MDAC 8.0 does.

I would probably build an install program that ensures that you have the correct MDAC release installed when your application is installed.

Without the same version of Access (or approximately so) they probably won't be able to run your app. Access '97 for example will not run an Access App developed with Access 2K+.

[small]No! No! You're not thinking ... you're only being logical.
- Neils Bohr[/small]

 

[dabruins]

Hi Golam.

I'm aware of the problems that exist for access users attempting to use a newer version of an access database. I'm planning on using a 2002 frontend which should allow users of A2003 access without any problem. I think we have a couple of 2000 users but we feel we want to upgrade those anyway. The users would have either Windows 2000 or Windows XP. The hope is to start moving away from 2000 and into XP in the near future. Older versions would at least move up to 2000. I think the versions on MDAC on all of these machines should include the ADO components and be somewhat similiar (MDAC verson 2.6, 2.7 or 2.8).

Suppose I did not use late binding and declared a ADODB.Recordset using MDAC version 2.8 during development. Are you saying that a user using MDAC version 2.6 would not encounter a problem when trying to create the same recordset object within their session? That is, is the instantiation of an object of the same namespace occurs regardless of the local version of MDAC?

I'm looking for a site that shows me the differences in ADO object models for different MDAC versions but I haven't stumbled onto it yet. Any ideas?

Is the version of MDAC available to a user restriced by the OS version? You've mentioned using an installer to upgrade the MDAC version so it would seem your not prohibited from doing so?

I know I'm going to be dealing with performance issues anyway and would like to use early binding if possible.

Thanks.

 

[Golom]

Sorta ... kinda ... maybe.

It really depends on what functionality you are invoking in your use of ADO. Likely simple recordset creation would not have problems since that's been fairly standard over several MDAC releases. If however, you are into disconnected recordsets or persistent ones (particularly XML) or some of the other more esoteric and recently added MDAC functionality, then you may have a problem with older releases.

You can certainly update the MDAC release installed on virtually any machine (at least Win 98 or later). Here's a whole buncha MDAC stuff including the downloadable installers.

You certainly can use early binding ... it's just that binding ... early or late ... won't absolve you of incompatibities associated with possibly brain-dead (for your purposes) MDAC releases.

[small]No! No! You're not thinking ... you're only being logical.
- Neils Bohr[/small]

 

[dabruins]

Yeah I'm not dealing with exceptionally complex circumstances in using the ADO components. I think I'll be pretty much in the safe area of ADO for many of the releases.

Thanks for the info and the link Golam. This has been exceptionally helpful.

PS. Great Neils Bohr quote!