Xbase++ DBF application to Upsize PostgreSQL application

[slobodan1949]

Alaska Xbase++ PGDBE engine is a specialized engine that converts an application made in the Alaska Xbase++ programming language into:

1. an application that uses a PostgreSQL database and SQL tables via commands:

UNIVERSAL SQL commands (embedded in PGDBE or ODBCDBE)
PGDBE SQL Commands (embedded PGDBE)
ODBCDBE SQL commands (built into ODBCDBE)

2. an application that uses a PostgreSQL database and SQL tables by translating that PostgreSQL database to a UPSIZE PostgreSQL database with a special program tool DBFUPSIZE.EXE via commands:

ISAM DBF commands (built into Xbase++ programming language and PGDBE)
UNIVERSAL SQL commands (embedded in PGDBE or ODBCDBE)
PGDBE SQL Commands (embedded PGDBE)
ODBCDBE SQL commands (built into ODBCDBE)

3. an application that simultaneously uses a PostgreSQL database and a DBF database, i.e. DBF files and SQL tables, by translating that PostgreSQL database into a UPSIZE PostgreSQL database with a special program tool DBFUPSIZE.EXE via commands:

ISAM DBF commands (built into Xbase++ programming language and PGDBE)
UNIVERSAL SQL commands (embedded in PGDBE or ODBCDBE)
PGDBE SQL Commands (embedded PGDBE)
ODBCDBE SQL commands (built into ODBCDBE)

Point 1. is the future of large business SQL Xbase++ applications.

Point 2. is a joyful and interesting future for developers of SQL Xbase++ applications.

Point 3 is life extension and improvement of existing large projects and investments in DBF Xbase++ applications, i.e. primarily protection of existing investments.



------------------ My idea for further work with Xbase++ applications ----------------



I have software (business application) FISCAL CASH FOR RESTAURANT done in Alaska Xbase++ 2.0 and eXpress++ with DBFNTX and ADSDBE database engines. The application belongs to a program that can be used anywhere in the world, because it deals with operational recording of sales in restaurants and issuing invoices to restaurant guests for the products sold. For this reason, I chose this application for this display.
The application has relatively simple business processes and business logic, but it has complex communication with the database and, in particular, it has a very complicated user interface.
Good side:
Under ADS server this application works great (fast and accurate). The interface made in Xbase++ and eXpress++ is very good. It works in a network environment. It works through the Windows RDP service, which means that it can be used over the Internet and Windows Server 2016 and beyond.
Bad side:
ADS Advantage Database Server is no longer supported in further development by SAP. The current application with DBF/DBT/FPT and NTX/CDX files and without ADS server and with ADS server is not a good solution when you need to connect to it via mobile devices working with ANDROID OS (waiters collect orders via mobile devices). It is also not a good solution when you need to send SMS messages from the application to selected guests in the existing loyalty system. Using a DBF database for some future translation of a desktop application to a web application (which is a trend) is always problematic and it is better to have a PostgreSQL database in that case. The DBF database still has a faller when it comes to UTF-8. Today, most things, especially REST web services, are transmitted via XML and JSON files that require UTF-8. The PostgreSQL server works with UTF-8 by default, and in Alaska Xbase++ PGDBE this is perfectly solved - so the programmer does not need to worry about it (this lack of DBF database is a problem for everyone who is not from the English speaking area and has their own special characters in to your character set).
Decision:
Therefore, I decided to migrate this application to a UPSIZE PostgreSQL database using the latest Alaska Xbase++ DBFUPSIZE and PGDBE technology. In doing so, I set the following goals:
1. Use a PostgreSQL Server that is small enough to be easily distributed with a business application.
2. Use a PostgreSQL server that can work with both 32-bit and 64-bit Windows and which can be easily and quickly installed by the application user.
3. Based on point 1 and point 2, I adopted PostgreSQL server version 9.4.4 to develop this application. This does not mean that the same application will not be able to work with newer versions of the PostgreSQL server. As I write this, the current version is 16.
4. Give up simultaneous work with DBFNTX, FOXCDX and PGDBE, that is, simultaneous work with DBF files and their upsize clones of PostgreSQL tables. Work only with PGDBE and PostgreSQL tables and maximally use existing ISAM commands and functions, which exist in the application, to communicate with PostgreSQL tables.
5. Give up emulation of NTX and CDX index files in UPSIZE PostgreSQL tables. It has been shown that indexes can be well created on PostgreSQL tables during the operation of the PGDBE application, and they can be replaced by other solutions from the powerful pastrough SQL language built into PGDBE. The same applies to the ISAM commands SET FILTER TO, DELETE-PACK, APPEND FROM, COPY TO, TOTAL TO ...
6. Write all very important commands and functions for working with the PostgreSQL database in passthrough SQL, which is built into PGDBE. Give up trying to simulate these commands and functions through the ISAM machine (it has not been tested long enough and various problems are possible). Write these commands and functions as special user functions, or as snippet code, so that they can be applied in any subsequent application.
7. In the course of work, collect and record all the problems that have arisen and all possible problems that may arise in the operation of the application.

8. Publish this project on the eXpress++ forum as a thank you to master Roger Dannay and many other participants of this forum for the good things I have received from them so far.

[slobodan1949]

PART 2

[slobodan1949]

PART 3

[slobodan1949]

PART 4

[Wolfgang Ciriack]

Hello Slobodan,
have you the possibility to give me a link for downloading the attachments ?
As always, i am not able to download them here from the forum.

[Auge_Ohr]

As always, i am not able to download them here from the forum.

click in Link and get Error

now "edit" URL and delete "/phpbb3" in URL-Sting to get File

[slobodan1949]

LINK

www.cobasystems.com/download_user/Alaska Xbase++ To PostgreSQL (Part 1-2-3-4).zip

[Wolfgang Ciriack]

@Jimmi,
Thank you, that way i get the files.
@Roger,
Perhaps, you can change the links to the attachments automaticly ?
Wrong: ...//bb.donnay-software.com/donnay/phpbb3/download/file.php?id=2243
Works: ...//bb.donnay-software.com/donnay/download/file.php?id=2243
@Slobodan,
Thank you for the link.

[slobodan1949]

PART 5a

[slobodan1949]

SOURCE CODE