A connection represents connection information of a specific database, and acts as the parent in the hierarchy for all physical tables and physical columns that are defined for that database.
Pentaho metadata models can connect to most common relational databases using JDBC. The Pentaho Metadata Editor (and the Pentaho metadata architecture) supports a vast and rich set of data sources. Before you begin defining your business model, you must first describe the database or data source that you would like to model. You do this by defining one or more connections in the editor.
Note: While the current implementation of Pentaho Metadata Editor supports multiple connections and multiple business models in
the same domain, each business model must use physical objects (columns and tables) from a
single connection only.