Yes, Oracle XE can be used as the DBMS platform to support an Enterprise ArcSDE geodatabase. Because of the DBMS limitations listed below, ESRI recommends that ArcGIS Server Enterprise and Oracle Express Edition (XE) should only be used together for developing and testing applications and not for production environments.
Oracle Database 10g Express Edition (Oracle XE) is a no-cost edition of Oracle Database 10g. It is built with the same code base as Oracle Database 10g R2 and is available for 32-bit Linux and Windows platforms. It is free to deploy and embed in custom applications and upgradeable to other licensed Oracle editions.
The Enterprise ArcSDE Post Installation wizard on Windows can be used to configure an Enterprise ArcSDE geodatabase on a single instance of Oracle XE. The full geodatabase data model and ArcSDE geodatabase functionality is available.
The Enterprise ArcSDE geodatabase is administered like other supported DBMS platforms with SDE commands and using DBMS management tools.
This implementation is supported by ESRI; however, it should only be used for developer/testing applications.
* Oracle XE memory usage is limited to 1 GB RAM on 1 CPU.
* Each Oracle XE database is limited to 4 GB in size.
* No DBMS support for the following: Oracle Data Guard, Oracle RAC, Oracle clusterware, Java, Java server pages, Web services, 64-bit Itanium operating systems, iSQL*Plus, automatic storage management, partitioning, OLAP, data mining, transportable tablespaces, and synchronous/asynchronous change data capture.
* Limited DBMS security, flashback availability, database backup options, change/configuration management, and database replication.