OpenVMS Boot Camp 2015
 
Migrating SQLMODs from Rdb to Oracle

Track: Database

Speaker
Denys Beauchemin, Account Executive, Sector7


Description
Migrating applications that use Rdb from OpenVMS to another platform means dealing with the interface used for database access. On OVMS programs can use embedded SQL calls or more commonly they make use of Rdb’s SQL Module Language, SQLMODs. These modules are separate from the application code and contain only SQL. The host language of the application makes calls to the SQLMOD procedures passing parameters to be used by the SQL language inside the SQLMODs. This methodology decouples the data access layer from the application code and also makes this layer reusable by any other application program requiring access to the data. When doing a migration, it is not unusual to have an application that may have many thousands of source code modules using a few hundred SQLMODs. These SQLMODs may each contain hundreds of related procedures used in various combinations by the application modules. While the SQL code in these SQLMODs is similar to Oracle’s SQL, it is not directly usable for Oracle access. Migrating these SQLMODs is the challenge that this presentation will address as we examine an automated tool that transforms these SQLMODs into objects that can be used by the application code to access Oracle without any code modification.

Experience Level
Intermediate