Trey,

Let's assume for a moment that the data store is a tier. I have not read any substantive material that includes the data store as a tier. However, that does not make that issue fact or fiction. So, let's go with it.

Since the definitions of the User, Business, and Data services are fairly well agreed upon, what would the requirements be for the data-store tier? Does any data store qualify? If so, a text file counts since a text file is a bona-fide data store.

I think at a minimum, the data store has to support a language. Further, the powers of the language have to be served to the outside world by the data store tier. Clearly, this would knock out a text file.

Would SQL Server pass muster? Yes. SQL Server is capable of exposing stored procedures to clients. You can have access to these items via ODBC, OLE-DB, etc.

Would Fox pass muster? I don't think so. Stored procedures are not exposed. There is a very limited subset of the language that is exposed in the ODBC Driver. Sure, you could write a DLL to accomplish a lot of this work. However, that would be in the context of a data-services tier, not the data store tier.

FWIW, I think this is the start of a convincing argument for why Fox-Data would not qualify as data-store tier - assuming such a tier really existed...

Assuming for the moment that the argument is bunk, is there a way we can construe that Fox-Data would count as a 4th. tier. You cannot use the USE statement since that is driven by the UI. You cannot use the USE statment in a middle-tier DLL since the UI cannot "see" the cursor. You could use ADO. However, if all of your tiers are in Fox, my question would by "why would you do this?" If you are in Fox anyway, why not take advantage fo what Fox offers?


Your thoughts...

< JVP >


>So,
>
>Tier 1 = Interface
>Tier 2 = Business Layer
>Tier 3 = Data Services
>Tier 4 = Database
>
>I'll see Doug's 3 and raise 1 <g>
>
>So what else but VFP can do all *4* tiers?
>