Create DDFs for Pervasive data files

Use the DDF Maker component from Steve Blank!!

Here are some tidbits from the last project I worked on.

Put some 2-3 letter indicator in front of each file name which will NOT be part of the DDF. Steven's DDF maker will present you with a list of filenames to include in the ddf, and marking the ones you have no intention of using in the DDF maker will make the process much easier. Since the DDF maker presents the file list in alphabetical order, I used "ZND" as my indicator. The "Z" made all of these files show up at the bottom of the list, and "ND" was my reminder of "No DDFs".

The DDF maker can NOT "update" ddfs, it can only create them. Each time you make changes to your data structures, you will need to re-create the DDFs. This isn't too difficult; but if you are using other external programs (for instance, Crystal Reports) which uses those DDFs, you may need to "re-synchrnoize" the external program stuff with the newly modified DDFs. In Crystal Reports, this is Database Menu, and must be done for each report.

Adding fields isn't too difficult. Deleting fields is a tad more difficult. Chaning fields is probably hardest of all. Also, changing the name of a field is probably more work than changing the attributes of that field. In particular, I am referring to the maintenance of Crystal Reports .rpt files.

Steven's DDF maker follows the same rules for assigning "Alternate Collating Sequence" information as the Magic eDeveloper. Only those fields which are Alpha AND used as a key segment are given the relevant ACS information. If you have additional Alpha fields which should be marked to use the ACS, you will need to modify the resulting DDFs manually. This is best accomplished in the PVSW Control Center.

Hope this helps!

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