Datafile Strategies for Migrating from COBOL to Java and C#
SoftwareMining's strategy for migrating from COBOL to Java and C# ensures that SQL databases and Sequential files are retained.
In contrast, VSAM and Indexed Files undergo transformation into an Object-Relational architecture and are then incorporated into SQL databases.
Below is the detail of this migration approach:
KSDS and indexed Files Files
Although many COBOL applications have transitioned from VSAM files to relational databases (COBOL with Embedded SQL), or adopted transaction handling libraries like CICS, numerous applications still rely on VSAM KSDS files for data management.
The optimal migration strategy would associate every field with a distinct column. Challenges can emerge from intricate REDEFINITIONS or multiple record File-DEFINITIONS. However, effective design can resolve such complexities swiftly.
Other considerations include handling data dispersed across several files, GDG support, and related concerns.
Performance considerations for the Java layer accessing the database are paramount. Although SQL databases excel in sifting through large datasets, data retrieval might lag if data needs to traverse a network, emphasizing the importance of proficient design in Java/C# code, databases, and data-access libraries.
Sequential files, typically employed for temporary data storage, can facilitate communication between programs, assist in sorting, or generate reports. By default, SoftwareMining retains these as files within the system, but they can be easily transitioned to SQL databases.
SoftwareMining-produced Sequential files offer:
Binary compatibility with COBOL-generated files, ensuring seamless communication with yet-to-be-translated modules.
A streamlined path to newer standards, such as MS Excel.
Relative Files
Relative files can either be preserved as files within the system or migrated to relational database tables.
Multiple File-Definition for the Same Datafile
Multiple programs within an application might designate varied structures (FILE-DEFINITION) for the same datafile.
This method works for Files but poses challenges when delineating database columns. Manually amalgamating such structures can be tedious and prone to errors. Automated identification and reconciliation of these definitions can be a cornerstone of successful migration projects.
Performance Focus
Batch programs are often time-bound. Therefore, performance significantly shapes the design of the migrated Java or C# code. Factors greatly influencing the performance of migrated code include:
Number fields: The translator should, where safe, convert COMPUTATIONAL formats to native Java data-types.
Precision: Java BigDecimal should only be deployed when imperative.
Removing redundant structures to reduce load time.
Parallelization is more feasible with clear and maintainable code (Java/C# post-migration).
REDEFINES: The translator's capability to identify and eliminate them.
