>>How do you plan on passing the cursors ? As XML ?
>
>I have not thought about that yet <g>. I thought I would create cursors in UI tier and they would be "visible" in BIZ tier. Therefore, "passing" would not be necessary. I realize this is not "true" n-tier design. But at this stage I just want to separate UI from BIZ so that I don't have to repeat code in multiple forms (as I do now).
>
>But please tell me if you have better suggestions. I would appreciate it.
At this time, XML is probably the ideal, since this would enable you to have your UI tier communicate with your BIZ tier over the Internet. It also allows you to switch in non-VFP tiers (eg. .NET) relatively easy.
There is nothing wrong with a migration path like the one you are considering; it may make things easier in the long run though if one has a long-term architectural plan in mind.
As for "binding controls to tables" in the UI, in the long term you can continue to do that in VFP: you just switch in "local" cursors/tables. This is known as running "disconnected", and that is how .NET operates.
And as you observed, there are performance implications in funneling data between tiers: while in file server based VFP we thought mostly in terms of "record and file oriented operations", n-tier is basically "set" oriented.
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