Provinzial realizes complete migration from IBM IMS/DB to IBM Db2 with Delta

With the tools and services from Delta Software Technology, Provinzial Rheinland finished the complete application and data migration from IBM IMS/DB to IBM Db2, automated and securely, of over 75 IBM IMS databases and over 36,000 artefacts.

Provinzial: Its Modernization Strategy

On their website, the Provinzial Rheinland writes: “Insurances are not sexy – we know that. But it is wise to make provisions.” And further: “The goal of our employees in the office and in the field service: create freedom in the lives of our customers by ensuring a holistic security.” The Provinzial also acts in the same way when modernizing their IT: Create good provision, security and freedom.

“The Delta solution has its advantages in two points that are particularly important to us: Due to the complete automation of the transformation, the ongoing development of the system, as requested by the business, was uninterrupted during the entire project. Due to the in-place migration and a parallel operation concept, we achieved absolute security and quality during the migration. The guaranteed operational “smoothness” in the project, despite the complex modernization, is certainly a unique feature of the solution.”
Stephan Kaiser, Program ‘sponsor’ Provinzial

The central IT systems of insurance company Provinzial Rheinland (Provinzial) are self-developed applications on an IBM mainframe. In the medium term, Provinzial wants to move to an open platform (UNIX/Linux). The first step in their modernization strategy is to migrate all applications and data from IBM IMS/DB to IBM Db2.

Due to the volume of the Provinzial application systems, the amount and complexity of the required changes, the tight schedule as well as their experiences with the manual conversion of some programs and databases, Provinzial decided on a tailor-made and fully automated solution with the tools from Delta Software Technology (Delta).

Successful Migration with Delta

With Delta’s solution, Provinzial was able to successfully migrate all applications and data completely and absolutely secure from IBM IMS/DB to IBM Db2 and … at a fixed price.

These advantages of the Delta solution were particularly important for Provinzial:

• Tailor-made solution: Provinzial was free to design the new data model and choose between alternative transformations. This allowed them to directly influence the performance of the applications and ensure that the new data model would be fit for the future.
• Complete replacement of IMS/DB: No emulation, but clean applications as if they had originally been developed with IBM Db2.
• No Freeze: The repeatability of the processes allows the undisturbed parallel further development and maintenance of the modules that will be transformed; blockade times were eliminated.
• Maximum security: This was ensured by the rule-based and automated implementation of all changes, meta-level tests (verification of the transformation rules and complete testing of the transformation results prior to the actual modification of the sources) as well as a continuous, completely closed process (“clean room”) from the analysis to the transformation - instead of implementation “by human hand”.
• Flexibility: Data and application transformation were decoupled and could be performed independently of each other.
• No “point of no-return”: In the case of new recognitions, extensions of the set of rules or new program versions, modules that had already been converted simply went through the transformation process again.
• Audit-proof: Every application and data transformation were automatically and completely documented.
• No follow-up costs, no “footprint”, no “vendor lock-in”: After project completion, there are no licensing or maintenance costs for tools or new runtime components.
• Implementation in-budget at a fixed price
  
  

“We were impressed by the efficiency and flexibility the AMELIO factory was set up and continuously optimised with. The very good and close cooperation with the Delta managers and employees also contributed significantly to the success of the project.”
Ralf Prediger, Provinzial Project manager

The Highlights of the Delta Solution

The change from IBM IMS/DB to IBM Db2 is a paradigm change that affects not only the storage of data, but also the entire program logic for the data accesses in all applications. In addition to the data transformation, extensive changes to the programs were therefore necessary. However, the functionality, interfaces and data structures were not allowed to be changed.

The following highlights describe how Delta met Provinzial’s high requirements.

Clean Relational Data Model and Migration of the Data

Due to the technological differences of the database models, implicit definitions of the accesses, structural features and others, a 1:1 transformation of the hierarchical system IBM IMS/DB to the relational IBM Db2 is not possible.

Delta determined the IMS data model that was actually used in the sources and data structures as well as all dependencies and interrelationships. A proposal for the new IBM Db2 data model was automatically generated from this information. On this basis, the experts at Provinzial developed the new relational data model, that will also meet future requirements.

The data model and the mapping rules created by Delta provided the basis for the transformation of the data as well as for the generation of the IBM Db2 accesses, so that changes to the data model automatically and identically affected the application and data transformation.

Service programs generated with Delta ADS were used to migrate the data from IBM IMS/DB to IBM Db2.

Fully automated transformation with AMELIO Modernization Platform

In an iterative process, Delta built a customised transformation factory for Provinzial with the AMELIO Modernization Platform. This factory works rule-based and fully automated according to a clean room concept. All changes are implemented consistently and audit-proof in all sources without any manual interventions. The transformations were perfectly tailored to the requirements of the project. Operational features, standards or special implementation rules for the performance improvement were also considered.

The complete automation of the transformation guarantees maximum security on the one hand, and on the other hand it enables flexibility and short reaction times for new requirements. In addition, the testing effort is drastically reduced by the rule-based working method.

Implementation of Data Services

Data services were automatically generated for the accesses to IBM Db2. They deliver the data and status values exactly as required by the programs - despite the paradigm change.

The logic of the programs and the interfaces were not changed, naming conventions and programming guidelines were considered. The decoupling of application and data accesses has the additional advantage that changes to the data model must not have any effect on the programs.

Extra Security and Flexibility through Special In-Place Migration

The migration was performed step by step as a so-called in-place migration. For this purpose, all data accesses were performed simultaneously on both database systems, i.e. for IBM IMS/DB and also for IBM Db2. For control purposes, a switch system was implemented that would have allowed the re-activation of the old system in production at the push of a button at any time in the case of an error. In this way, all data could be compared automatically and all programs could be verified - and not only in the test environments, but also in the productive environments.

Subsequently, AMELIO CleanUp Factory was used to remove again all code components for accessing IBM IMS/DB and for the switch control of the in-place migration step. The result is clean sources, just as if they had originally been developed for IBM Db2.

“Thanks to Delta's transformation strategy, Provinzial succeeded in migrating absolutely securely from IBM IMS to IBM Db2. At the same time, this solution gave us absolute flexibility, as components that had already been transformed and those that had not yet been transformed could be used productively together without any problems.”
Ralf Prediger, Project Manager of Provinzial

Performance

The change from extremely fast IMS databases, whose application programs are often precisely aligned with the storage structures, to the more flexible Db2 databases, which are suitable for ad-hoc requests, often leads to losses in performance. Provinzial also feared this. However, due to the automated migration and the possibility to individually adapt the transformation rules, there were no performance losses. The specifications for the performance of the migrated applications were met to Provinzial’s complete satisfaction: A goal that was achieved in particular thanks to the good cooperation with the Provinzial project team.

Delta Tools for Tailor-made fully automated Migration

The following tools from Delta Software Technology were used for the fully automated transformation of the applications and migration of the data:

• AMELIO Logic Discovery
  The comprehensive assessment of the applications with AMELIO Logic Discovery provided the information on all the project's sticking points, for the migration strategy, a precise planning and the reliable cost calculation.
• AMELIO Modernization Platform
  The tailor-made, fully automated transformation with AMELIO Modernisation Platform guaranteed the consistent and audit-proof migration of the applications.
  In this project, AMELIO was also used to gain additional security and flexibility in the project through in-place migration.
• AMELIO CleanUp Factory
  Clean, fully automated removal of all superfluous code.
• Delta ADS
  Automatic generation of the data transformers for the migration of all data from IBM IMS to IBM Db2.
  
  

The Company Provinzial

The Provinzial Group is a public insurance group. With a gross premium volume of more than 6 billion Euros, it is one of the ten largest German insurers. The former Provinzial Rheinland Versicherung AG (Provinzial Versicherung AG since the end of 2021 following the merger with the westfälische Provinzial), which is headquartered in Düsseldorf, offers its private and corporate customers products and advice on all insurance topics, including home, liability, motor vehicle, accident, life, pension, occupational disability, health, long-term care, legal protection, and more.

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Further Informations

Hier finden Sie weitere Artikel zum Thema:

• Gothaer Systems starts migrating its IBM IMS Databases
• Automatically replacing IBM IMS/DB
• Successfully Replace IMS Databases
• IBM IMS/DB? Modernization Now!
• Modernization Project at BSQ Bauspar AG
  
  

24th GI Workshop "Software-Reengineering & Evolution"

The 24th Workshop "Software Reengineering & Evolution" of the GI specialist Group Software Reengineering (SRE) took place this year from May 2nd to 4th, 2022.

GI: 24th Workshop Software-Reengineering & Evolution
02.-04. May 2022, Bad Honnef, Germany

Dr. Daniela Schilling presented a concept and the solution as well as its utilisation by Delta's client RDW in order to make applications quickly and safely fit for the future at the 24th Software Reengineering & Evolution workshop of the German Informatics Society's (GI) special interest group on Software Reengineering (SRE):

"A Washing Machine for Software - Automated Clean-up of Technical Debts"

Abstract

RDW has been developing and maintaining vehicle management applications for more than 30 years. The applications work reliably, but over time technical debts have accumulated that make maintenance and further development difficult. The daily business as well as the size and criticality of the application do not allow a manual clean-up of the software. The solution of the problem: a washing machine that automatically cleans the software from the technical debts.

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Our Speaker

Dr. Daniela Schilling
Dr. Daniela Schilling is Managing Director of Delta Software Technology.

Further Information

“The Gesellschaft für Informatik e.V. (GI) is the largest and most important professional society for computer science in the German-speaking world. It represents the interests of computer scientists in science, business, public administration, society and politics. Become part of this lively network!”

Further information on the event can be found here:
https://fg-sre.gi.de/veranstaltung/24-workshop-software-reengineering-evolution

You couldn't attend? Then contact us, we would be happy to meet you for a personal discussion.

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Support Information: New Product Version of Delta ADS available

We have released a new version of our generative development system Delta ADS for COBOL. With the release 6.5.1 a new optimisation option for the code generation has been implemented:
Using the option OPT-L, you can have the control code for iterations be optimised.

Do you already know the option OPT-O?
Using this option will optimise the generation of control statement and thus will minimises the generation of GOTOs.

In addition, we have released a new version of our plugin ADS on Micro Focus Enterprise Developer (7.2.4).

You can find more information about new features and fixes in the release notes at the support area of our website.

Get information and updates right now. You’ll find the list of our current product versions here.

IMS Replacement: In Time – In Budget – In Scope

Gothaer Systems migrates its IBM IMS Databases to IBM Db2 together with Delta Software Technology.

Automatically migrating from IBM IMS/DB to IBM Db2 was Gothaer Systems' task. The goal of operating only one database system on the mainframe brought Gothaer Systems and Delta Software Technology together. Delta offered the solution of know-how, suitable tools and services for this task. By building a tailor-made factory with the AMELIO Modernization Platform, the necessary steps for the transformation could be implemented automated, well calculated and at low risk.

Gothaer’s motives

The maintenance and costs of two database management systems on the mainframe (IBM z/OS) are expensive, tie up resources and slow down innovation. The knowledge or knowhow carriers about IMS/DB will soon retire and young developers in this field are hardly available. For these reasons, Gothaer Systems (Gothaer) sought to migrate its IBM IMS/DB stored data to new IBM Db2 structures. The IMS/DB calls in existing database access programs (COBOL and Delta ADS) were to be implemented automatically in such a way that the IMS databases were completely replaced. The runtime behaviour and the performance of the converted programs were not to be impaired.

“By migrating from IBM IMS/DB to IBM Db2 together with Delta, we have successfully mastered the next big step in the ‘Smarter Mainframe’ project.”
Burkhard Oppenberg, CIO, Gothaer Systems

Due to the volume, the scope of the required adaptations, as well as a tight timeframe, a manual transformation did not seem advisable. High demands were placed on the quality of the adaptations to be implemented in order to reduce the test effort and duration. These requirements were met by an automatic transformation. For this purpose, Delta Software Technology (Delta) used the AMELIO Modernization Platform (AMELIO) and built a tailor-made transformation factory for Gothaer.

Advantages of the Delta Solution

For Gothaer, the following advantages of the Delta solution were particularly important:

• Tailor-made (automated) transformations
• Transformations can be retraced and reproduced at any time.
• Further development and maintenance are not impaired
• No freeze periods
• No foot-print or vendor lock-in, hence no follow-up costs for licensing
• Implementation in budget with a fixed price
  
  

Large-scale Project successfully completed

Transformation of programs and data models according to customer requirements

At the beginning, all applications were analysed for data accesses and an initial set of rules was defined for how the new Db2 accesses should look and how affected code should be transformed. In addition, proposals for the relational data base models were created by Delta and coordinated with the Gothaer. Data services for the data accesses and data transformers were then generated from the models fully automatically.
Thus, in close coordination between Gothaer and Delta, the AMELIO Modernisation factory was successfully trained and continuously expanded. Coding standards and specifications by the DB administrators were also considered. During the setup phase, the regular maintenance and further development continued at Gothaer. The resulting new versions of source modules were included into the ongoing AMELIO work. After successful transformation of the applications, they were handed over to Gothaer for meta-level testing and release.

Approval and Test of the Applications

To verify that the factory was working correctly, an application test was performed based on the meta-level test concept. This concept is based on the fact that if the factory correctly implements a rule once, it will always implement it correctly. With a factory approach, the tests can therefore be limited to a test set of representative test cases that cover all analysis and transformation rules. As a result, Gothaer was able to drastically reduce the testing effort and save expensive testing time.

“With Delta, we have found a reliable partner. A constructive cooperation with ideas and ‘short paths’ has made this project a success.”
Stephanie Bethmann, Project Management

Conversion of Data Access and Data Transformation

The changes in the COBOL and ADS programs should be as small as possible. For this reason, the accesses to the Db2 databases were outsourced to data services generated by Delta. In doing so, existing data services from Gothaer were used. This decoupling of application and data access has the additional advantage that not every later change to the database model has a direct impact on the calling programs.

Based on the new data models, data transformers could also be created fully automatically, which transferred the data from IMS/DB to Db2.

In 2 Years from IMS/DB to Db2

The conversion was implemented in manageable packages and not with a big bang. In 2 years time, all requested IMS databases and all of their data and applications have now been successfully transformed to Db2 and are in productive use.

“As ProjectOwner, I am particularly pleased that the well-calculated IMS/DB replacement with Delta went so smoothly and on time, and that the result is convincing across the board.”
Michael Buchwald, ProjectOwner

The Project from Gothaer's Point of view

The Gothaer is more than satisfied with the project, all work carried out at a fixed price. They appreciate the flexibility with which Delta responded to challenges and how easy it was to provide the factory with changed versions. The performance was considered and optimized together in order to be able to guarantee the usual performance with Db2 as well, and thus to achieve the best performance potential of the applications.

In addition, the new data models meet the current requirements, they are future-proof and enable new and more flexible accesses. For example, attributes can now be addressed individually in SQL queries instead of using predefined keys.

The meta-level testing is also mentioned prominently - massive cost savings could be realized here, since each change did not have to be viewed manually.

The entire migration project ran smoothly and without any downtime – on the contrary: Gothaer was able to further develop the applications in parallel.

At Gothaer, the replacement of old technologies is a further step in the modernization of its IT landscape. The complete connection of today’s operative systems on the host - in the context of new projects - is made much easier and makes a decisive contribution to the digitalization and the accelerated implementation of new technical requirements.

About Gothaer Systems

“Gothaer Systems is the central IT service provider of the Gothaer Group. We ensure that Gothaer is always at the cutting edge of information technology: through innovations and continuous further development of technology and organization. We also provide the infrastructure for accessing data and business processes. This is how we ensure a high level of IT quality within the Group - and thus support Gothaer’s business.”

Get to know AMELIO and Delta

Due to the high degree of automation, transformations can be repeated, comprehended and reproduced at any time. Freeze periods are reduced to a few hours. The migration can be divided into packages and the result is applications that can be continuously used and maintained without footprint and vendor lock-in.

• Would you like to learn more about modernization projects or are you planning refactorings?
• Do you want to migrate an application package to a new platform?

Like Gothaer and other customers, go the well calculated, secure and perfect way with Delta and consolidate your database systems. We would be happy to show you the possibilities offered by the AMELIO Modernization Platform. We are looking forward to your contact.

Download Success Story

Futher Informationen

Here you can find more articles on the subject:

• Provinzial realizes complete migration from IBM IMS/DB to IBM Db2 with Delta
• Automatically replacing IBM IMS/DB
• Successfully Replace IMS Databases
• IBM IMS/DB? Modernization Now!
• Modernization Project at BSQ Bauspar AG
  
  

SVA Mainframe Dayz 2022

SVA Mainframe Dayz 2025

In February 2025, the focus will be on the mainframe again!
A variety of presentations, exciting discussions and, above all, lots of field reports from the world of the mainframe await you on February 18th and 19th, 2025 at the Mainframe Dayz in Wiesbaden.

Delta Software Technology is represented with a lecture. On February 19th, 2025 at 1:10 p.m., Dr. Daniela Schilling presents:

"When the English Dictionary is not enough - Understanding Applications with AMELIO"

Regular maintenance, extensions, clean-ups or modernizations - no matter what the task is, without a thorough understanding of the application there is no chance of success. COBOL language is easy to read, but that alone is not enough to actually understand large and complex applications.
Do you want to know how AMELIO Logic Discovery helps you to regain knowledge about your application by means of automated analyses, abstraction and task-specific views?
Then come to our lecture at the SVA Mainframe Dayz on February 19th in Wiesbaden.

Further information, registration and agenda can be found here: https://www.sva-events.de/event/MainframeDayz2025/

Join us and take the opportunity to exchange ideas with your colleagues and discuss current topics.

Register now!

Review: SVA Mainframe Dayz 2023

In March 2023, the focus will be on the mainframe again!
A variety of presentations, exciting discussions and, above all, lots of field reports from the world of the mainframe await you on March 7th and 8th, 2023 at the Mainframe Dayz in Wiesbaden.

Delta Software Technology is represented with a lecture. On March 7th, 2023 at 1:15 p.m., Dr. Daniela Schilling presents:

"Automated Application Cleanup: Using the Washing Machine for Software"

Be there and take the opportunity to present yourself with your colleagues and to shed light on current topics.

Also read about this:

Review: SVA Mainframe Dayz 2022

From March 9th to 10th, 2022 we were at the SVA Mainframe Dayz 2022 in Wiesbaden, Germany!

Delta Software Technology were present with a booth and presentation. On March 9th, 2022 at 2:30 p.m., Dr. Daniela Schilling:

"Successful Automatic Database Migration at Gothaer: In Time - In Budget - In Scope"

You could not attend? Here you can request the presentation slides.
Only available in German. If you are interested in an English version, please contact us directly.

Review SVA Mainframe Dayz 2021

In a monthly event series, the Mainframe SpeakZ, SVA again gave the mainframe a voice. With a diverse mix of customer presentations, industry news, tool updates, and more, SVA keeps you up to date on all things mainframe.

Delta Software Technology was there with a presentation:

"Application modernisation according to your requirements, parallel to ongoing operation"

Dr. Daniela Schilling (CEO Delta Software Technology) explained sticking points and pitfalls in large modernization projects and showed solutions based on a large project at a leading German insurance company.

Contents

The foundation of business-critical applications has often evolved over decades. During this time, the applications were changed and further developed. New technologies were introduced, partly without completely removing the old technologies.

Modernisations such as clean-up, refactoring, technology exchange and standardisation as well as platform migration are necessary to meet new requirements, improve performance and maintainability, and increase the sustainability of the backend applications.

The documentation of the applications and the knowledge about what was implemented and why it was implemented that way has been lost over time.

• So, how do you regain the required implementation knowledge?
• What do you do with the dependencies?
• What about the risks?
• How do you find all the sticking points?
• How do you organise parallel changes and further development?
• What must be tested?
• How do you securely manage (testing) efforts, costs and risks?
• ...

The solution lies in the precisely targeted analysis prior to a modernisation project, the complete automation of the changes and the flexible organisation of the project processes.

Referencing a large project at a leading German insurance company, we show you how you can safely and reliably carry out a complex modernisation of your applications in parallel to ongoing operation in the mainframe area.

Slides and Recording

You could not attend? Here you can request the presentation slides and watch the recording.
Only available in German. If you are interested in an English version, please contact us directly.

New: ADS on Eclipse Release 8

ADS on Eclipse is Delta’s modern, integrated development environment (IDE) for the efficient development and maintenance of COBOL and PL/I applications written with Delta ADS.

The new ADS on Eclipse Release 8 is available now. It offers improved functionality for the development and maintenance of applications written with Delta ADS.

ADS on Eclipse

ADS on Eclipse supports your development teams with specialised features that enables them to deliver new functionality to your business users faster and with better quality.

• Clearly arranged perspectives to display the corresponding areas and views in the IDE
• Modern editor with intelligent editing and debugging functions such as automatic syntax check, chroma coding, code completion and templates, outline views, bookmarking, code folding, documentation and much more
• Direct integration of the application generators, so that dependencies and build precedence are checked
• Post-generation debugger for step-by-step tracking and testing of the generating process with direct switching between code editing and debugger.
• And more …

Working with ADS on Eclipse improves the understanding of your applications as the generators provide additional information about the application components.

Furthermore, ADS on Eclipse enables the seamless integration of application development with Delta ADS into the entire development process.

New in Release 8 for ADS on Eclipse

Release 8 is now available for ADS on Eclipse. It contains numerous innovations.

• Configuration and deployment: Improved handling of configuration and deployment of the installations.
  Companies increasingly use central deployment software to automate the provisioning of workstations. This gives them security and simplifies administration and support through uniformly designed work environments.
  ADS on Eclipse Release 8 now help to significantly reduce the administrative effort, especially in larger installations when using central deployment software.
• Eclipse Release 2022-03: With Release 8, ADS on Eclipse now supports Eclipse Release 2022-03, making ADS on Eclipse available for Eclipse Releases 2019-12 up to and including 2022-03.
• Java 17: With Release 8, ADS on Eclipse now also supports Java 17, making ADS on Eclipse available for Java Long-term Support (LTS) Releases 11 and 17.

For more information, see the release notes for ADS on Eclipse Release 8.

What else …

The integrated development system Delta IDS is not only available in the variant ADS on Eclipse, but also for other systems such as Visual Studio, Micro Focus EDz, IBM IDz, LzLabs LzWorkbench.

We will soon provide ADS on Visual Studio for Visual Studio 2022.

ADS on Eclipse for you

You too can benefit from the power of ADS on Eclipse. Work with the new ADS on Eclipse to provide your business users with new functions faster and with better quality.

We would be pleased to help you, please get in touch with us.

The Best Environment for Your Application Development

Support information: New Product Versions available

Today we have released new versions of the following products:

• ADS for COBOL & PL/I (6.5.0)
• ADS on Eclipse (8.0.0)
• Generator Engine (6.5.3)
• License Management (3.0.0)

You can find more information about new features and fixes in the release notes at the support area of our website.

Get information and updates right now. You’ll find the list of our current product versions here.

New Delta Training Courses: Register Now

Anyone using tools to automate software development needs in-depth knowledge of the methods, modes of operation, and capabilities of the tools. And not just "in principle", but in relation to the concrete environment and task.

Our training courses and workshops help you to use Delta tools efficiently and to optimise the development of your applications: Practice-oriented and taking into account your main areas of interest.

ADS Basics - ADS for Administrators - ADS Refresher - ADS on Eclipse - ADS What's new

Here you will find the new dates:

• 03.03.-05.03.2026 and 15.09.-17.09.2026 - ADS Basics
• 10.03.-12.03.2026 and 22.09.-24.09.2026 - ADS for Administrators
• 17.03.-18.03.2026 and 29.09.-30.09.2026 - ADS Refresher
• 14.04.-15.04.2026 and 06.10.-07.10.2026 - ADS on Eclipse
• 21.04.2026 and 13.10.2026 - ADS What’s new
• 28.04.2026 and 20.10.2026 - Delta DETAB

Learn more about our trainings and workshops ...

Contact us to discuss your requirements for a customised training.

45 Years Delta ADS

Delta ADS turns 50

Developing software is looking to the future, but sometimes it is good to turn around and look back.
As we did, we discovered that the foundations of our products were made almost half a century ago.

Delta ADS - Review

This year, 2026, we celebrate 50 years of Delta ADS. In this years newsletters we will look back on the history of Delta ADS and reflect on its features that have contributed to its long lasting success.

Half a century ago, programming a computer was a special kind of magic for most people. It also was an individual and very creative process with pen, paper and punch cards. Getting complex programs functioning correctly was a difficult and time-consuming process and came with considerable costs that did not allow for the compiler to be used for error finding.

The use of terminals to write programs was a big improvement in the development process. It provided a better overview of the program logic without having to compile and print a listing first. This overview was limited of course by the maximum of 24 lines a terminal was able to show at the same time. This was not sufficient for complex decisions which gave rise to the first tools to support the programming. Although such tools were available for many programming languages, the main field for these tools was in the area of the most widely used programming language for business applications: COBOL.

1971: The First Idea

In 1971, Dr Reinhold Thurner of Zürich University published about the use of decision tables in the software development which led to DETAB/GT to generate the programming code based on a more abstract definition language . By 1976 DETAB/GT reached 100 installations, the same amount of installations was achieved by its competitor VORELLE².

Generating a complex decision structure for COBOL programs was a great help, especially when keeping in mind that in these days COBOL statements were terminated by a single point and complex decisions could easily run over 24 lines of code. It also showed that effective programming needed more. A major step was not in the use of tools but in the way, programs were structured. In an environment dominated by card readers, tapes and report writers (hard disks were expensive and had only limited capacity), each program depended on the structure of the input and output data. The fact that each programmer used his or her personal style and creativity did not make the maintenance of these programs easy. Some kind of craftmanship and best practices was needed. This led to a number of Structured Programming initiatives. The most widely used was Jackson Structured Programming (JSP)³ that Michael Jackson published in 1975.

At the same time Dr. Thurner launched a generator system that, based on the principles of structured programming, was able to produce much of the needed code. It used an abstract description of the structure of the data, in a language specifically defined for that task. The product was called DELTA⁴. It solved the problem that Dijkstra addressed in 1968. The programmer did not need to program and maintain any GO TO statement, only the generator produced them for the executable program⁵.

Over the years, Delta (later called Delta/ADS) was extended with a number of standard generators for standard functionality in Business Programming. PSD (Program Schema Description) and GRU (Control Break Processing) helped programmers to keep an overview of their programs and to focus on the unique functionality they have to implement while not being bothered by mechanisms needed to implement it.

Platform independence - Thanks to Generators

A major step in the development of Delta ADS was the concept of platform independence by the use of generators and macros. Back in the old days, each mainframe (compiler) had its own deviations of the COBOL standard. A program written for platform A was thus not usable on platform B without changing the source code. Not a big deal if you develop your software inhouse for your own use but it is for a software supplier that wants to install his software on many platforms. The use of the generators and macros in Delta ADS to deal with the platform specific aspects of the implementation meant that a program for many different target platforms could be maintained in one single source code object.

Platform independence did not only benefit software suppliers but after some time many Delta ADS users discovered that this possibility also facilitated a platform migration. The fact that an existing application could be migrated easily to a new platform when using Delta ADS is an important reason why many installations are still actively used, some for over 40 years, and that Delta/ADS is still alive and kicking after 50 years.

“I am pleased that after 50 years, Delta ADS is still being used successfully
for the development and migration of large and complex applications.”
Dr. Reinhold Thurner

 The Future - and beyond

Like Delta DETAB, Delta ADS for COBOL and PL/I remains a part of our product portfolio. Over the years an estimated 2+ billion unique lines of code have been generated with our generator system, a number that is still growing each year. Initially, DETAB and Delta ADS were only available for the platforms for which they generated code.

Today they are also integrated into modern development environments such as Eclipse or Visual Studio and can generate cross-platform.

As the advantages of this generative approach to software development is still valued by our customers we remain committed to supporting them with our tools. The current release 6 of Delta ADS will certainly not be the last as we will continue to find solutions for the challenges our customers experience in their software development process.

50 Years of Delta ADS: Supporting the Developer

This year, 2026, we celebrate 50 years of Delta ADS. In our first retrospective we focussed on the techniques that played a big role in the area of code produce. Now we will look into another important part of Delta ADS, besides producing code: supporting the developer with tooling, prototyping, documentation and testing.

The first domain that Delta ADS took care of is the production of documentation. During the generation process, a number of different sorts of documents can be produced. Depending on the Delta ADS processors used, e.g. a program flow chart is created, an overview of all available locations and their usage becomes available and, last but not least, SPP has the option of generation a Nassi-Shneiderman diagram of a SPP-routine.

All these features enabled the developer to check the actual program against the design he made. But being able to communicate with the end-user about the results of a program has always been an important but difficult issue. Results could only be shown after running the program which needed a functional program and available data. Adapting afterwards was a tedious and error prone process. Therefore, Delta ADS allows for prototyping of reports and screens which produce the simulated results during the program generation. This gives the feedback at a much earlier stage, reducing the effort to correct the implementation.

Correcting existing programs has always been an important, time consuming but undervalued part of a programmer’s job.

Delta’s founding father Dr. Reinhold Thurner already found out in an early stage that: ‘for the correction of an error, 20% of the effort is needed to determine that there is an error and to pass the issue to the correct people. Next, in terms of time consuming, is to find the component that causes the error. The effort needed to fix the error is very often limited (but as we are in a hurry we tend to introduce new errors)’.

In a time where interactive debuggers were not available, finding an error was often a case of inserting display statements in the code to see where the program was when the error occurred. After fixing the flaw, these display statements had to be removed again. When another error came up, this process had to be repeated again.

Using a generator for the code produce opened up a solution for this time-consuming process. By activating one of the TEST-options (for the complete program or just one SPP-routine), the program will protocol each passed SPP-construct. This gives the programmer the much-needed insight in what a program did at runtime (and much faster compared to debugging) without having to program display-statements for that.

Additionally it can also produce statistics showing what logic was executed during the test run, giving an idea about the validity of the test and about general test coverage.

From the start, Delta ADS aimed at supporting the programmer to produce structured, well documented and maintainable code. A mission that we, after 50 years, remain to continue.

History

Article from Computerwoche, January 10, 1975 - Delta Author Dr. Reinhold Thurner:
"Multifunktionales Generator-System für moderne Software-Technologie: Ein Superding für die Avantgarde"

Sources

¹ Thurner R., "Entscheidungs-Tabellen: Aufbau-Anwendung-Programmierung", VDI- Taschenbuch T33, VDI Verlag, Duesseldorf, 1971.

² Jeweils 100mal installiert:: Vorelle und Detab/GT | Computerwoche, 02.07.1976

³ Jackson, MA (1975), Principles of Program Design, Academic.

⁴ Multifunktionales Generator-System für moderne Software-Technologie: Ein Superding für die Avantgarde | Computerwoche, 10.10.1975

⁵ Dijkstra, Edsger W. (March 1968). "Letters to the editor: Go to statement considered harmful" (PDF). Communications of the ACM. 11 (3): 147–148. doi:10.1145/362929.362947. ISSN 0001-0782. S2CID 17469809.
p. 147, "The unbridled use of the go to statement has as an immediate consequence that it becomes terribly hard to find a meaningful set of coordinates in which to describe the process progress. ... The go to statement as it stands is just too primitive, it is too much an invitation to make a mess of one's program."

AMELIO Logic Discovery - 'Nicholas'-Release

AMELIO Logic Discovery helps you to (re) understand your large and complex COBOL, PL/I and ADS applications. The two new perspectives “KnowledgeBase” and “CallTree” speeds up this process.

KnowledgeBase – Finding instead of Searching

With the KnowledgeBase perspective, you get an overview of all analysed artifacts at the push of a button. You can quickly and safely find the access to the modules that are relevant for your task.

Furthermore,

• You get analysis information on groups of artifacts as well as on each individual artifact
• You will find out which (code) patterns were found and how often, both for the entire application, for groups of artifacts or just individual artifacts
• You can use the comment function to record findings and make them available to others
• With the bookmarks and tags you get the possibility to mark artifacts of particular interest to find them easier
• With intelligent filter functions, you can simply focus on the artifacts that are relevant to the current task
  
  

Query Technology

The new query technology expands the KnowledgeBase perspective and provides you with exactly the modules that are relevant for your task. In addition to the ready-made queries, you can now easily define your own queries with the query builder.

Overview in the Application Network

One question that always recurs is to identify dependencies in the network of artifacts: Who is calling whom and who is being called by whom? AMELIO Logic Discovery provides that too at the push of a button. The new CallTree perspective is the counterpart to the established ProgramTree perspective. For a program, it shows the other programs from which it is called.

And beyond,

• You receive information about the program interfaces, which parameters are expected and which are actually transferred
• Decision tables show you clearly and unambiguously which conditions must be fulfilled to enable a program to be called.
  
  

Ensure the Success of your Project through optimal Application Analysis with AMELIO Logic Discovery

Do you want to (re) understand your application, carry out a migration or modernization project?
Or get rid of technical debt from your applications?

AMELIO Logic Discovery helps you with this and automatically provides all the information you need. Try it.

You can find more information about AMELIO Logic Discovery on our website ... or just contact us directly.

Also read ... 

SVA Mainframe Dayz 2021

SVA Mainframe Dayz 2025

In February 2025, the focus will be on the mainframe again!
A variety of presentations, exciting discussions and, above all, lots of field reports from the world of the mainframe await you on February 18th and 19th, 2025 at the Mainframe Dayz in Wiesbaden.

Delta Software Technology is represented with a lecture. On February 19th, 2025 at 1:10 p.m., Dr. Daniela Schilling presents:

"When the English Dictionary is not enough - Understanding Applications with AMELIO"

Regular maintenance, extensions, clean-ups or modernizations - no matter what the task is, without a thorough understanding of the application there is no chance of success. COBOL language is easy to read, but that alone is not enough to actually understand large and complex applications.
Do you want to know how AMELIO Logic Discovery helps you to regain knowledge about your application by means of automated analyses, abstraction and task-specific views?
Then come to our lecture at the SVA Mainframe Dayz on February 19th in Wiesbaden.

Further information, registration and agenda can be found here: https://www.sva-events.de/event/MainframeDayz2025/

Join us and take the opportunity to exchange ideas with your colleagues and discuss current topics.

Register now!

Review: SVA Mainframe Dayz 2023

In March 2023, the focus will be on the mainframe again!
A variety of presentations, exciting discussions and, above all, lots of field reports from the world of the mainframe await you on March 7th and 8th, 2023 at the Mainframe Dayz in Wiesbaden.

Delta Software Technology is represented with a lecture. On March 7th, 2023 at 1:15 p.m., Dr. Daniela Schilling presents:

"Automated Application Cleanup: Using the Washing Machine for Software"

Be there and take the opportunity to present yourself with your colleagues and to shed light on current topics.

Also read about this:

Review: SVA Mainframe Dayz 2022

From March 9th to 10th, 2022 we were at the SVA Mainframe Dayz 2022 in Wiesbaden, Germany!

Delta Software Technology were present with a booth and presentation. On March 9th, 2022 at 2:30 p.m., Dr. Daniela Schilling:

"Successful Automatic Database Migration at Gothaer: In Time - In Budget - In Scope"

You could not attend? Here you can request the presentation slides.
Only available in German. If you are interested in an English version, please contact us directly.

Review SVA Mainframe Dayz 2021

In a monthly event series, the Mainframe SpeakZ, SVA again gave the mainframe a voice. With a diverse mix of customer presentations, industry news, tool updates, and more, SVA keeps you up to date on all things mainframe.

Delta Software Technology was there with a presentation:

"Application modernisation according to your requirements, parallel to ongoing operation"

Dr. Daniela Schilling (CEO Delta Software Technology) explained sticking points and pitfalls in large modernization projects and showed solutions based on a large project at a leading German insurance company.

Contents

The foundation of business-critical applications has often evolved over decades. During this time, the applications were changed and further developed. New technologies were introduced, partly without completely removing the old technologies.

Modernisations such as clean-up, refactoring, technology exchange and standardisation as well as platform migration are necessary to meet new requirements, improve performance and maintainability, and increase the sustainability of the backend applications.

The documentation of the applications and the knowledge about what was implemented and why it was implemented that way has been lost over time.

• So, how do you regain the required implementation knowledge?
• What do you do with the dependencies?
• What about the risks?
• How do you find all the sticking points?
• How do you organise parallel changes and further development?
• What must be tested?
• How do you securely manage (testing) efforts, costs and risks?
• ...

The solution lies in the precisely targeted analysis prior to a modernisation project, the complete automation of the changes and the flexible organisation of the project processes.

Referencing a large project at a leading German insurance company, we show you how you can safely and reliably carry out a complex modernisation of your applications in parallel to ongoing operation in the mainframe area.

Slides and Recording

You could not attend? Here you can request the presentation slides and watch the recording.
Only available in German. If you are interested in an English version, please contact us directly.

The Best Environment for Your Application Development