On 6/20/06, MB Software Solutions <[EMAIL PROTECTED]> wrote:
Is there a "best strategy" for migrating an existing, in-use app from VFP to a non-VFP backend (in my case, MySQL)?
Much better - thanks! There are a lot of best strategies, one per situation (the old consultant "It Depends" ploy). Ideally, you have a fully normalized application and you have been using some consistent method to manage the data. Views, CursorAdaptors, your own custom data manager class, whatever. In the best of all possible worlds, you add another driver to your data manager that knows how to talk to MySQL. You convert a "batch" of data tables from DBF to MySQL - a batch being a set of densely related tables with more connections between them than to the outer world, like all the A/R tables, for example. A module. Then, you tell your data manager to use its remote driver to talk to A/R instead of the DBF driver. MSFT used to dog and pony this with changing all the local views (lv_customer) to remote views (rv_customer) with no other changes needed to the system. I've seen Andy Kramek do the same with his data classes, and Doug Hennig show off similar ideas with CursorAdaptors. In the best of all possible worlds, that's a nice idea. Years ago, converting one web site from DBF to SQL server, I changed all the inline code to calls to a data manager to return a cursor for processing. Then I added a table with columns for "DBF SQL" and one for "SQL SQL" and when I'd converted them all, I switched. It works. Luck happens like that, once or twice in a lifetime. The devil's in the details, of course. If you have RI between the two systems, you're going to need to hand-code that. And transactions between the two backends can be an issue, which is why you'd like the "module at a time" technique above. -- Ted Roche Ted Roche & Associates, LLC http://www.tedroche.com _______________________________________________ Post Messages to: [email protected] Subscription Maintenance: http://leafe.com/mailman/listinfo/profox OT-free version of this list: http://leafe.com/mailman/listinfo/profoxtech ** All postings, unless explicitly stated otherwise, are the opinions of the author, and do not constitute legal or medical advice. This statement is added to the messages for those lawyers who are too stupid to see the obvious.
