637d0961   
   From: contact@harganonline.com   
      
   On Sun, 17 Aug 2008 15:12:16 -0700 (PDT), dwightarmyofchampions@hotmail.com   
   wrote:   
   >. There's no "link" between   
   > Transactions and TransactionDetails. I know there's a much MUCH easier   
   > way to do this via the Paradox 9 program instead of C++.   
   > Unfortunately, I don't really know how to use that.   
      
   What Larry said. Plus, I though I'd actually answer your question! ;-}   
      
   Yes, there is a much easier way to do this in PDox9. If you create your app   
   wholly within Pdox9, and abandon C++ altogether, creating tables with RI is   
   trivial -- but comes with *BIG* potential problems.   
      
   First, here's how you do it. Create the two tables using File/New/Tables --   
   the dialog is self-explanatory. Be sure to create the primary index by   
   putting the index fields first and putting an asterisk in front of them   
   (this will be clear when you see the dialog). NOW, re-open this dialog for   
   the subtable -- you do this with Tools/Utilities/Restructure. The far right   
   tab is "Referential Integrity". Use this to link it to the parent table.   
   That's it!   
      
   Now for the problems. Paradox is the Tounces of the RI world. It does it --   
   just not very well. The big problem is that the table directory paths are   
   HARD CODED into the structure, right down to the drive letter. If you move   
   either table, your whole application breaks. This makes Paradox RI   
   effectively undeliverable. For a one-person standalone application it does   
   what you want -- until you decide to buy a new computer. Then you have to   
   EXACTLY duplicate the drive and directory structure on the new machine. And   
   don'd even THINK about rearranging your hard drive.   
      
   Most of us just do RI in code, which is pretty easy once you are used to   
   Paradox's powerful language, OPAL, specifically structured for a RAD   
   database environment.   
      
   And that's the second problem: OPAL is a very odd language, and C++ by   
   itself will only help you a little. OPAL uses pointers a lot, much like   
   C++; but it is designed to look like Pascal; and it is event-driven, like   
   JavaScript in a browser. You cannot create new classes or objects   
   programmatically. Instead, you define all your objects interactively, then   
   hang code onto them ONLY as it is needed to modify their default behavior.   
   The trick is to learn the default behavior (which is VERY subtle and   
   complex) and only then learn what code you need to change this.   
      
   The reward: once you internalize this, Paradox is the ultimate RAD (except   
   for the RI problem of course). But, as both OPAL and the BDE have been   
   deprecated, is it worth your while? Did I mention that Paradox does not   
   have a Vista-ready version?   
      
   If your choice is learning Paradox from scratch vs Access or Foxpro,   
   Paradox is, IMHO, the better choice -- simpler and more powerful despite   
   its problems. But that's not your choice, is it?   
      
   --   
   HTH   
      
   Jim Hargan   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)