Oracle still has more users on Windows than Linux, though that is dropping. Some 60 percent of respondents run a database on Windows, a figure expected to fall to 48 percent by next year. Windows 2000 is the most popular platform, followed by Windows Server 2003.

Heterogeneous environments dominate, with only 7 percent of respondents running pure Oracle shops; 70 percent also run Microsoft's SQL Server, up from 41 percent who said that in a 2001 survey. More than half also run Microsoft Access, and more than a quarter run IBM's DB2, up from 18 percent who said they did so in 2001.

MySQL, the fast-growing open-source database, is used by a quarter of Oracle users, mostly as a front-end caching database to support external queries, the survey found.

Not only are environments heterogeneous, they're also scattered. Almost of half of users reported that they run more than 20 Oracle databases at their sites. The median database is 50GB in size, and one in four is larger than 1TB.

The expected migration of Oracle 9i, the five-year-old database still widely used by respondents, to Oracle 10g over the next year will give many users the chance to consolidate. Implementing grids and clusters is much easier in Oracle 10g, Kaplan said.