Migration Tips: DataEase 6.x to 8.2x onwards
We get a lot of request on migration, and it can be a minefield.
We are currently working on conversion filters for extended characters which has been a show stopper for many of our international customers.
Due to compatibility with DFD the PRISM part of DFW ran the original character set of DFD while the GUI bit used the WIndows Character Set for a country like Norway for instance that would be:
CodePage 865 for DOS and OEM (ANSI) for Windows.
The translation of this was handled through an obscure string in DEMESSAGE.MSG which converted between the character sets. This insured that all languages had a workaround to run their old DFD data together with DFW 5.x and 6.x
In the big "updated" done with 7 this was removed so that PRISM (Data and Tables etc) would now run the same character set as the GUI. The migration handle this through a conversion table from ANSI to the new Windows standard codeset for Western Europe 1252.
All good so far,but when PRISM and GUI is not in the same character set this is disaster, and it was.
An attempt was made at some stage (abandoned? or at least very un-shared) of including a file called convert.mig that should alleviate this problem, but 1) It is undocumented and not shared knowledge. 2) It doesn't work.
So typical of many of the improvements put forward in 7.x ...
When we say it doesn't work we mean that it will convert data, Table Names and Column Names and the legible part of Derivations and scripts but not the compiled part so it looks to work, but in reality it doesn't.
However it might have been a create help for in-house consultants in DE (which it might have been intended for, rather than the wider public, so so much of the useful improvements made during this era) as they could then simply touch each table and DQL and recompile without having to manually change names etc.
Anyway, beware this is another obstacle on the route to migration "heaven"..
However, we will publish a short "guide" on how to successfully migrate from DFW 5.x/6x to DFW 8.2 onwards. DO NOT MIGRATE TO DE7.x!
DataEase 8.x is fully compatible Windows 7.x through Windows 8.x and is currently being tested in Windows 10, so far without any problems.
You can migrate any DFW 6.x application to DFW 8.2 or later. It will in most cases be completely straight forward, but there is a couple of things you need to bear in mind:
1. Extended characters.
If you have used extended characters in your tables, columns, derivations there might be conversions issues between 6.x and 8.2x. We are currently looking into this and will soon publish an updated including different translations for successful migrations.
2. Base year
Make sure you set the base year in your DataEase 6.x application to 75 before you start.
3. Date Format.
Do not select from Configuration. Select the correct format you have used ex. Dd-mm-yy. If you get a lot of trouble in migration with illegal date it is due to either 2 or 3. Just change the settings and try over.
We re-introduced Menu documents and old Style memo in DE8.2 so it should be a 1 to 1 migration, but as with all migrations there might be situations and code that is not covered.
With DataEase 8.5 we for the first time since 7.0 have a version of DFW that vastly outperform earlier DFW versions so there should be no reason to hold back due to the earlier experienced performance problems identified with DFW 7.