Transitioning Foxpro-Prolog 3

[amros]

Hello all,
I have never worked with FoxPro-Prolog languages. However, I am assigned a project that will help convert this project to the latest language.
The problem here, in addition to being a newbie, is that the version of FoxPro that is currently being used is version 1.8
The project is that, FoxPro 1.8 has the DB, some 20 odd DBF files. And then there is a prolog script that runs in the foreground. There are at least 15 prolog scripts and I do not have any idea to the sequence of these scripts. Each of this script is about 300o lines long.

The UI is a DOS based screen that the user enters values. Based on those, calls to some tables are made. Some complicated statistical calculations are done on this data which then gets inserted into these tables.
The complexity of this program is high. Also what complicates it further is that there is no documentation at all, which make my life so much fun. The people that are currently working with this program, have no idea about the tables, what is there in the tables and the logic for the script. All they know is what data to input and what screen comes up next and what to do in that screen and then print this information.

The computer, on which this project is running, has never been updated for the fear of breaking this program. I have a couple of dilemmas:
1. If I extract the data from the FoxPro databases and start writing the program from scratch it would take tremendous effort and not to mention the fact that the people actually using this have no idea what is happening. To get the logic, I would have to talk to an in house scientist, which I hope has some idea,

So, I am hoping that is there a way I could use this program in today’s environment. Maybe write a script in windows environment that actually has its own UI, but when u click a button on the new UI, it calls the old program, or in essence actually connects to the old screen and that in turn calls the FoxPro. So I would need something that could compile this combination of FoxPro and Prolog.


2. The second would be to extract the FoxPro information and bite the bullet. I managed to extract the data from all the tables expect one which has 250,000 rows or such. The method that I was using was that, open the DBF file in excel. Save it as excel and then open it in access. I can’t do that in Excel since Excel allows only 65000 rows. All the remaining data is lost. If I open the file directly in Access, by using the import option it gives me a error “Unexpected error from external database driver”. I think its giving me the error since the oldest version of DBF files that is there, is DBF III. And the version of my file is older than that. So I need some advice as to how to get the data put of there.


3. Also, any documentation on FoxPro 1.8 or Prolog. And how those two works together would be very helpful.

Has someone done a project like this? If yes, what was the strategy?
If no, what would be the best possible strategy to go about this project.
I would appreciate any guidance of any sort.
I am pretty clueless at this point.
I appreciate any help.
Thanks in advance
Rosalia

 

[JRB-Bldr]

While a vast majority of us in this VFP forum would likely recommend staying in VFP, there are a couple of different perspectives to take into consideration.

1. Company long-term perspective. It will be easier in the future to find software developers in languages other than VFP.
It is a fact that over the years the number of VFP developers has diminished making it more difficult (not impossible) for companies to find individuals to maintain/enhance their existing VFP applications.

While there is no denying this fact, it may or may not need to be a make-break decision factor. Consider how long the application of your DOS version of FP worked before any thought was made about changing it.

2. Public perception of VFP.
* While largely inaccurate, many people equate Visual Foxpro with Foxpro (DOS & Win31 versions) and consider it to be an OLD technology product. That perception would be comparably inaccurate as equating Visual Basic or VB.Net with its predecessor Basic.

Certainly some applications may be OLD and may have been created with OLD versions, but VFP 9 is most certainly not an antiquated product - in fact in quite a few ways it technically rivals or exceeds the competition.

* Microsoft did indeed declare that they will not be creating a new version of VFP beyond the current version 9. That scares a number of corporate individuals. But VFP9 is still being sold as a current product.

3. If you were going to change languages, Access would be the LAST one that I personally would consider.

Yes it is free and sometimes thats all that matters to the decision makers, but it would be a poor choice. It is the 'little brother' product among the database application development languages. It would be like considering the use of a Ford Pinto when possibly needing a Ford 350 Pickup.

First - there is NO code migration path from FP to Access or VBA or VB. Most especially from FPD 1.8

That means that ALL of the code, computational and other would need to be created from scratch in the new language.

You would first need to fully understand the FP app code and then create all of it in the new language.
If you were going to go to that much effort in a non-VFP language, I'd recommend going with .NET Basic (as you suggest above) or C#

Many people have 'up-scaled' their VFP product by migrating their VFP data into SQL Server. There are a number of good reasons to consider doing that and the transition does work. However with differing data field types, different data access mechanisms, etc. it forces the introduction of a number of changes to the code.

My Short term goal: get the application working on XP
Long term goal: get the forms looking a little better

Taking YOUR goals into consideration...

* Running the existing code in a DOS window under XP would achieve the first goal in the most simplistic manner.
* Migrating the code into VFP would be the smoothest and easiest route to meet the second goal.

Depending on the complexity of the application, you could be looking at a likely LONG development effort to migrate the existing code into another language - thereby not achieving YOUR goals.

However your Company's goals or your Boss' goals might be somewhat different so they would need to 'buy into' the possibility of a lengthy re-development effort if they want you to change languages.

I get the sense that the directions have not been clearly laid out.

Before any talk of 'what language', 'where data should live', 'timelines', etc. occurs, the project priorities need to be clearly spelled out and there needs to be 100% buy-in by ALL parties involved.

Then with the priorities clear, options can be weighed and decisions can be made as to language, data repository, etc. with full recognition of the resulting consequences.

Good Luck,


JRB-Bldr
VisionQuest Consulting
Business Analyst & CIO Consulting Services
CIOServices@yahoo.com

 

[mmerlinn]

From my perspective, the "cost" in both time and money to go to Access vs VFP9 would be prohibitive.

Sure, the Access program may be free, but the cost of a program pales to insignificance when you figure in the cost in manhours to study the existing code, understand what the existing code does, and then rewrite that code to work in Access.

As noted many times above, VFP9 in the long term is probably the CHEAPEST way to go. And it is definitely the EASIEST.

That does not mean that VFP9, IN YOUR CIRCUMSTANCES, is the best way to go. Only you and your bosses can determine that. But if money is the MAIN motivating factor, VFP9 wins hands down.

mmerlinn

http://mmerlinn.com

"Political correctness is the BADGE of a COWARD!"

 

[NasibKalsi]

Hi Amros:

Access may be cheapest way to if you are buling a small application and from scratch. But Converting existing Fox application to Access is far cry. Basically I feel that you require to take a introductory course offred by many FoxPro experts. It may sound expensive, but beleive me, you will save tons and tons of time and bring your project faster to completion. Even, if you have to do in access, it may still be very helpful to take a course in access. PLEASE NOTE THAT I AM NOT ASSOCIATED WITH ANY OF THE FORUM MEMBER NOR I OFFER ANY TEACHING COURSES FOR FOXPRO. Foxpro is an easy language as many members have expressed, but require the basic understanding of the structure and constructs.

I applogise if I have repeated some of the ideas already expressed.

Good Luck

 

[Stella740pl]

Foxpro is an easy language as many members have expressed...

Who said that? I sure didn't. I said that transitioning an existing FoxPro project to Visual FoxPro is an easiest way to go to make it look and feel modern. (I think that's what most people who posted in this thread meant.)

 

[NasibKalsi]

Hi Stella740:

I stand corrected.

 

[amros]

Hello Dave, JRB-Bldr and Stella,
I was wondering if any of you guys would be available for doing this project for a fee of course.
The reason I say this is b'cos, the time spend on this project by any one of you guys would be far less than the time spent by me, due to my lack of experience.
If any of you guys are interested, please do let me know and we can discuss this further.
I again, want to thank you guys for all your suggestions and advice.
Regards
R

 

[JRB-Bldr]

Rosalia,

If you look at the bottom of this Forum page you will see a white box titled "Link To This Forum".

Within that box is a statement...

DESCRIPTION: Microsoft: FoxPro (old versions 1 to 2.6) technical support forum and mutual help system for computer professionals. Selling and recruiting forbidden.

Consequently if we were to offer our services via a Tek-Tips forum it would be in violation of our agreements for using of this forum.

Good Luck,


JRB-Bldr
VisionQuest Consulting
Business Analyst & CIO Consulting Services
CIOServices@yahoo.com

 

[amros]

Thanks JRB-Bldr!
Novice user
Will refrain from doing that

 

[amros]

Hey guys,
just wanted to give u guys an update..
we have just placed an order for Visual foxpro 9.
Thanks again for all ur help and guidance.
regards
R.

 

[JRB-Bldr]

Good Luck.

There are ways of using the web to find help for your conversion project without using the Tek-Tips forums should you be so inclined.

Even if you use assistance for the initial effort, it will never hurt to have your own copy of VFP9 so that once the conversion is complete you have the tools in-house to maintain/modify it yourself.

Again, good luck,


JRB-Bldr
VisionQuest Consulting
Business Analyst & CIO Consulting Services
CIOServices@yahoo.com

 

[Stella740pl]

Rosalia,

Glad to hear that you are getting started. Good luck to you.
Make sure you read Help provided with VFP - it is a great source of information. You can always come to the VFP forums to search for FAQ and threads on your topic and ask questions should you find yourself stuck.

If you would like to use outside assistance, you can try to find consultants/contractors either locally or over the Internet - or, possibly, some members may be available if you contact them through other means, like their web sites. Still, if you do so, I agree with JRB-Bldr, you will need your VFP copy for maintenance, modifications, and possible adding features in the future, etc.

All the best to you.