Case story
Written by Carsten Trolle, International Product Manager
Background:
Logstrup is a manufacturer of modular enclosure system for LV switchgear and control gear assemblies.
The end products are typically one-off and each of these engineered/configured to order. The complete list parts for each assembly consist of a large number of both structural or mechanical parts manufactured and supplied by Logstrup as well as electrical devices from 3rd party suppliers.
To manage and facilitate the vast amount of parts and possible combinations of parts we have made a product configurator consisting of a visual design part (LogCAD) combined with a database application (LogCalc).
The configurator is used not only internally by Logstrup but also by our customers which are independent partner panel builders scattered almost all over the world.
Logstrups history with DataFlex.
The LogCalc part of the configurator has always been based on DataFlex. This means all the way back to the ver. 2.3b DOS version and the days where everything could be found in the blue hardcopy books for user manual and commands (the old-timers in the Data Access community will know what I am referring to ).
Our main reasons for choosing DataFlex back then were the embedded native database structure and the fact that even with our limited internal programming skills we could actually code a robust and efficient application, which was tailor-made to our (changing) requirements.
Well, that is not entirely true: whenever things got too complicated we have also used the option to turn to the local Dataflex community for guidance on how to crack the hard nuts.
Another nice feature with Dataflex was the deployment; we could visit any of our customers, bringing a hand-full of floppy disks and set-up the configurator at the PC’s of their design engineers and sales/estimators.
Since we are not ourselves in the software business, the approach in all the years has been: if it works, don’t fix it.
Therefore we tend to be “last-movers” when it comes to migrating to the newer versions of Dataflex. We only started with VDF5 (sometime in the beginning of this century) because our internal and external users demanded a Windows-like user interface.
We sticked to VDF5 for a long time until the Windows print drivers did not support that anymore, and here we are today with a nice and well-functioning DF19.1 version of LogCalc.
LogCalc application in brief:
It consist of only around 20 tables, the main ones being:
- Library of Logstrup part numbers and BOM structures (around 30,000 records and growing)
- Library of groups of items, as a hierarchy of BOM’s – one record for each BOM line (around 75,500 records and growing)
- Main Project file, data are created by users
- Assembly file, data are created by users
- plus various other files to support specific tasks and engineering calculations
There is a total of 4 .exe files within LogCalc application, one main file and 3 smaller ones for specific purposes.
I will try to avoid being too boring by describing on the exact functionality of LogCalc, the essential part is that it is a mix of data supplied and maintained by Logstrup and data supplied and maintained by the users.
Even the two first mentioned libraries are also open for users to add and change data if they require.
Additionally it does happen that some users have multiple sets of datafiles, f.ex. one located at their local hard-disk (for off-line working) and another located on a company shared network drive.
The challenge:
LogCalc is used both internally and externally by what can best be described as ordinary users, who most often don’t want to spend time with system maintenance and ensuring that the application itself and all their relevant data are up to date.
The data supplied are dynamic by nature: prices are updated on regular basis, new part and groups of parts are added continuously.
The application itself was also from time to time improved and bug-fixed, which should be distributed to all users in coordination with data updates.
And worst of all: adding fields to existing tables or new tables, don’t even think about it.
In short it became and increasingly difficult and time consuming task both for Logstrup and the users to keep the all the installed systems up and running.
And in case you would ask: No, a web based application has not really been considered as an feasible alternative. The project specific data at the external installations would be considered commercially confidential by our customers, and they would not be comfortable sharing those with Logstrup or anybody else.
The Solution:
At the DataFlex forum we came to know about the DUF created by RDC Tools, Nils Svedmyr.
After contacting Nils he made a brilliant solution, incorporating a lot of nice features:
- Selection of datafiles as an option when starting the application
- Changing datafiles during a session
- The DUF (by RDC Tools) for updating database structures at external installation sites
- A robust and secure method for updating both program and datafiles at external installations.
This was complicated to make but yet so easy to use
This has saved a tremendous amount of time spent at maintenance of this application, not only for Logstrup, but especially our customers.
As a bonus we also got a most needed “brush-up” of the complete user interface of LogCalc without losing the functionality and basic working routines familiar to our long-time users.
As conclusion this is a credit to this work done by Nils (and over the years also by Sture, Torben and Allan), to the DataFlex application development tool and to the unique nature of the DataFlex community.
This is a very strong combination which allows us amateur programmers to link up with the hard-core experts and create a tailormade and very specialized tool, which still have the look and feel of professional and robust application.