IBM's DB2 Universal Database Express-C is available for Linux and Windows and can run on up to two dual-core processor servers with up to 4GB of memory. The software has no limits on concurrent user connections or on database size, unlike free databases from Oracle Corp. and Microsoft Corp. Those databases can only run on single-processor machines.

The new IBM database can be put into production use and embedded in third-party commercial software offerings and is available for download at www.ibm.com/db2/express/.

Curt Monash, a database analyst in Acton, Mass. and a Computerworld columnist, applauded IBM's release of a free DB2 that is limited by memory size, rather than the number of users or the database's size. "How much this drives the adoption of DB2 is a different matter," he said. "Every vendor, whether tradtional or open-source, has to have an essentially free low-end offering. At least it should help them propagate DB2 in mixed shops where they already have a foothold. It also should help them drive experimentation with their native XML capabilities."

But Jerry Murphy, an analyst at Westport, Conn.-based Robert Frances Group Inc., said "IBM is coming a little late here to counter what Microsoft and Oracle have already done, in terms of having a 'free' offering that works in limited environments."

IBM first released an Express version of its DB2 software in 2003, aiming the less-expensive database software at smaller organizations willing to trade scalability restrictions for a lower price. The new, DB2 Express-C software lacks a handful of features found in DB2 Express, including DB2 Warehouse Manager tools, Informix data source replication and DB2 Connect support for extending enterprise data to applications. Customers interested in support services from IBM will also need to upgrade to one of IBM's commercial DB2 options.