Glenn,
1. Virtualized tables are just one of the ways to access data on Cloud Pak for Data. You can also create connections directly to remote data sources, like Db2, and add tables as data assets. You can add files, like CSVs, from your local system. See:
Adding data to a project (Watson Studio and Watson Knowledge Catalog). For ETL, you can use DataStage:
Transforming data (DataStage).
2. A data fabric is an architecture for providing access to data without moving the data and an integrated set of tools for getting value from data. A catalog is the part of the data fabric where you share data assets. Here's more information about a data fabric on Cloud Pak for Data:
Data fabric use cases.
I hope that helps!
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Inge Halilovic
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