Real World Advice: Handling Mainframe Field Expansion
Blog //29-07-2021

Real World Advice: Handling Mainframe Field Expansion

by Rob Anderson, Vice President of Marketing and Product for Application Modernization

This blog navigates the mainframe field expansion process, and how our solution reduces the time and risk associated with COBOL modernization.

Mainframe field expansion is an inevitability that all IT administrators face during the process of maintaining large information systems. While the concept is simple, the changes it introduces are enormously complex. Architects commonly overlook the importance of an array size, data type, or system constraint in the design phase. By the time the limitation impacts the function of the business, the system and the inventory it manages may be enormous, resulting in a long and risky undertaking. In short, this effort impacts business logic, database access, application code, maintenance patterns, and much more. Mainframe field expansion is an unavoidable part of growth, and demands its place in your legacy technology support plan.


Mainframe Field Expansion: Can You Cope with the Scope?

So you have just realized that the primary key field used across all of your mainframe applications is about to be "too short" to accommodate a new business requirement. Understanding what software must change to accommodate this field expansion involves diving deep into the core application - and all others it touches. In addition, the analysis you do today will likely be flawed because the applications that require change are constantly being updated to support your business. DO NOT underestimate the level of analysis required. If you can get to the point where you feel the analysis is complete, the tedious task of making the software changes for the expanding fields requires a team of coders and a lot of time. Testers are also required and when you finish the project (many dollars later) you will still wonder what you missed.


Know the Details, Reduce the Risk

Although field expansion remains an almost unavoidable task in the maintenance of legacy systems and the businesses they support, the task can be complex and risky. These threats can be reduced drastically by automating the analysis, identification, and changes associated with a field expansion, ultimately providing return on investment through:

  • Removing barriers for growth
  • Continuity of key business processes
  • Easier application maintenance
  • Increased insight into data handling and managing capabilities of the legacy system


Automation is Your Salvation

Our Mainframe Field Expansion service leverages automated technology to reduce the time, talent and money required for the expansion of fields in your COBOL applications.

  • Field Change Manager services keep you in full control while speeding the expansion analysis and instantly applying, after your approval, hundreds of changes across thousands of programs and millions of lines of code. When the process is complete, you can be assured that all of the code available was analyzed and that all changes approved were applied.
  • The Field Change Analysis Engine performs the same analysis that your teams would perform manually, except that it can process hundreds of lines a second, can execute 24-by-7 if needed, and can repeat the entire process any time. Once the Field Change Analysis Engine completes its processing, your teams will be able to review all lines of code that will be impacted by the field expansion and review all additional fields that are affected by the field expansion – making changes where necessary. The process takes place over a matter of a few weeks rather than requiring many person-years for completion.


Further Resources

Blog Application Modernization ABM Application Analyzer Application Modernization and Migration OpenVMS Application Understanding Assessment COBOL Gen Lang IB-Arm OpenVMS VME Application Modernization Application Modernization and Migration Application Modernization Strategy Application Re-architected and Reintegration Application Understanding OpenVMS
Rob Anderson

Rob Anderson


Vice President of Marketing and Product for Application Modernization

Rob Anderson is Vice President of Marketing and Product for Application Modernization. He has spent the better part of the past decade developing, marketing, and selling mainframe modernization solutions, and has had a front-row seat in the transformation of the industry and its surrounding ecosystem.

Read published articles