Database migration is a decision that is most often made only after the resources needed by the current database system are no longer available. We then provide database selection alternatives and clear explanations as to the strengths and weaknesses of the possible replacements.
One of first concerns is to make sure the new database system being considered has widespread usage and reliable support. A healthy market share indicates that the product has a large following and the technical experts to support it will almost always be available. We usually guide clients to selecting a database product that has a substantial corporation ultimately responsible for support and development of the system. Selecting a product with that is not first tier often results with the product no longer supported by a current version of the operating system, or the product no longer being offered, or the database no longer meeting the needs of an increasing data load. We want to make sure that clients avoid the problem they sometime come to us with - a database system that is no longer functional with the business having instituted stop gap measures in order to continue operations.
The database migration process is straightforward – but many organizations make the mistake of treating it as if it were a new development project. New development projects typically start with database construction followed by data entry screens and then reporting. Data migration projects should always start with data transfer routines written simultaneously with database construction. The new system must obviously be able to accommodate the same data as was being gathered previously. We often find that data conversion needs to be added to the data transfer process as newer database systems support more appropriate and more precise data types. The data conversion programs may also need data validation logic as it is critical that the logical limits of the data be verified. After the data is imported to the new system, reporting functions need to be added to verify that the data transferred properly and that reporting from the new system is consistent with the old reporting.
Our data migration projects usually entail moving data in to either MS Access or MS SQL Server.
If you are unsure of which DBMS to deploy see the information on MS Access vs SQL Server.