for Creating Virtual Copies of CA-IDMS Databases
ASG-Virtual DB allows an organization to create multiple virtual copies of IDMS databases for use across a broad range of environments. It reduces the amount of DASD required to support multiple database copies and breaks through the limitations inherent in partial data and simulated test cases.
A virtual database is a self-contained copy of an existing database. The self-contained image looks like an actual IDMS database and is transparent to IDMS, its utilities, and application programs. You can perform all database functions against the virtual database. Under a virtual database, the existing database is protected from update. All updates are written to a shadow file instead of to the existing database. As a result, multiple users or groups of users can work with independent shadow files and thus have the ability to share a single existing physical database with no coordination effort or data integrity issues. Virtual DB also allows a shadowed view of the production database from the QA or test CV and although it uses only a small differential changes VSAM file, the entire production database can be viewed through it. This allows a programmer to instantly recreate production problems from the test system using the exact data that their user used.