What's the difference between Standard Edition and Enterprise Edition?
The differences are in three main dimensions: server size, features and available options. This discussion refers to the different editions of Oracle10g only.
Standard Edition can be run on a single server or server cluster with a maximum of four CPUs. There is no CPU limit for Enterprise Edition.
Standard Edition does not include a number of features of Enterprise Edition, including data compression, bitmapped indexes, transportable tablespace export, change data capture, summary management (materialized views and refresh mechanisms, among others) and parallelization of operations such as queries, DML and index creation. High availability features such as DATA GUARD, FLASHBACK, online table and index maintenance are provided only in Enterprise Edition. In the realm of information integration, Oracle streams and advanced replication are not supported by Standard Edition. Finally, Virtual private database and fine-grained auditing are available only in Enterprise Edition. Note that this list is not complete; for details, check the Oracle10g documentation set or MetaLink note 271886.
Several extra-cost options are available only with an Enterprise Edition license. They are advanced security, data mining, label security, OLAP, partitioning, spatial, the programmer interfaces for database development and the various enterprise manager packs (change management, tuning, diagnostics and configuration management).