Following are the some Features in Sql Server 2005:
1. integration of your back-end systems and data transfer across firewalls using XML.
2. Scale your applications up to 32 CPUs and 64 gigabytes (GB) of RAM. SQL Server 2005 has demonstrated record-breaking performance that you can leverage.
3. With SQL Server 2005 you can implement merge, transactional, and snapshot replication with heterogeneous systems.
4. Online Operations (Index Operations and Restore)
5. Snapshot Isolation
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