Your information systems are still sometimes based on hierarchical HDBMS or network NDBMS like DL1, IDMS, IDS2, or pseudo-relational like DATACOM …
For reasons of maintenance, support, interoperability, availability of competent resources or simply costs, it becomes necessary to migrate to a standard relational RDBMS.
Moving from a hierarchical or network DBMS to a relational DBMS asks a number of questions:
- The kinematics of the programs, based on a particular data organization must be modified, while maintaining the performance level,
- Queries, often very numerous in an application heritage must be rewritten,
- The data must be transferred to the new DBMS respecting the typing constraints and possibly the EBCDIC to ASCII conversion
Identical functioning of the system after migration must be checked