I would divide Xcelsius into 2 major Categories.
1. Dashboarding using Crystal Xcelsius Pro
Top 3 Skills needed: MS Excel (Intermediate Level), Xcelsius Pro and MS Excel again
2. Dashboarding using Crytsal Xcelsius Workgroup
Top 3 skills needed: Xcelsius Workgroup, Datawarehouse Reporting services and MS Excel.
The reason you need Datawarehouse reporting skills with Xcelsius workgroup is because here you are dealing with live data. Xcelsius workgroup can connect to a variety of live data sources using XML feeds, Webservices etc. Some of the datasources include SQL Server, BO Universe, Oracle Database etc.
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