VSAM

VSAM

Migration of VSAM files to any one of the main stream relational DBMS

Overview

MigrationWare provides a solution to the migration of VSAM files to any one of the main stream relational DBMS including SQL Server, DB2 and Oracle for deployment on and off the mainframe. New database structures are derived from existing VSAM record structures automatically considering and reconciling the differences in structure that could lead to incompatibility.

A data access layer is provided that separates the data access from the business logic and reconciles the new relational structure to the old VSAM record structure. In this way a standardised interface between the business logic layer and data access layer can be provided ensuring that the application logic is not affected by the necessary changes to the database.

Key facts

  • ​Highly automated solution.
  • No runtime dependency or dependencies on “black-box” technology
  • No license and maintenance fees are charged
  • Provides for separation of business logic from data access logic
  • Automatically handles occurring data items, Group level, Redefined data, and multi-record files
  • Targets DB2, SQL Server and Oracle on mainframe or distributed platforms
  • Code Conversion

    All access statements embedded in the program code are automatically replaced with standard executes to the new access layer, the source code of which is delivered as part of the conversion.

    The conversion of the database automatically handles multi-record files, redefined data items and group levels. Occurring fields either result in a child table or are expanded into the main table depending on the conversion criteria agreed with the customer. The result is a normalised relational database with appropriate indexes and keys being automatically generated.

    Because the input to the generation of the target DDL are the VSAM record definitions field names are automatically derived from the original structures. Changes may subsequently be manually applied to these, if required.

  • Database Conversion

    Data conversion modules are automatically generated. These modules are generated one per VSAM file, and take as input the VSAM file producing as output the database load file. Data may be converted to ASCII if the target database is to be deployed in an ASCII environment.

  • Conversion Process

    The conversion of VSAM will impact programs and databases. The process requires as input all program source code and copybooks.

    With this as input, the conversion process will produce a new version of programs, a new set of DDL and the programs responsible for the migration of data.

    VSAM files may be accessed from COBOL, Easytrieve, DYL280 and Assembler programs. In addition JCL is also impacted by changes. MigrationWare will address the impact of VSAM migrations on all of these programs in parallel with any possible language conversion.