Though this a free offering from IBM, Express-C is limited in it feature set. Listed restrictions include;
- Maximum processors: 2
- Maximum addressable memory: 4GB
- Database Partitioning Feature N/A
- Connection Concentrator N/A
- DB2 Geodetic Extender N/A
- Query Patroller N/A
- Net Search Extender N/A
Should you require a DB2 data server with more advanced features and 7x24 support from IBM, DB2 Express-C can be seamlessly upgraded to DB2 Express, Workgroup and Enterprise Server Edition(s) without modifying your database or your application.
The word from IBM is that they are looking to nullify cost as a factor in the decision making process used to decide with DB to use. Another consideration was the developer mindshare that mysql has captured. But is it still possible for IBM to recapture mindshare from developers by offering Express-C as free software?