The major differences between business views and universes are
Multiple data sources versus single data source A business view can have multiple data sources defined within it; a universe has one and only one connection. Although a universe connection can be dynamic, the universe itself can point to only one data source at a time.
Tip
Data from multiple universes can be combined within a single report as of Business Objects XI Release 2.
Reuse of business elements In business views, the business elements (which are roughly equivalent to the object classes) are reusable within other business views. Although object classes are not reusable, there is a similar functionality with universes in that universes can be linked. This means that a universe can embed another universe within it. The inheriting universe assumes that all tables and object definitions, and new joins will need to be drawn to integrate those tables with the existing ones in the inheriting universe. However, the inherited universe and inheriting universe still assume a single connection, meaning all tables exist within a single RDBMS.
Report variables as objects In business views, you can define an element that will not reflect a SQL snippet, but might be a formula composed of two or more elements that are SQL snippets. For example, there could be a revenue element that points to a column in a database, and a costs element that also points to a column in the database. From these two elements, there could exist a third element called margin, defined as revenue cost. When the margin element is chosen, the business view understands that the revenue and cost elements must be selected, and the formula executes within the Crystal Reports engine after the data is returned. In a universe, all objects are SQL snippets; you cannot place what is effectively a report variable in the universe.
