Typically, you create views of the source data (instead of tables) because views ensure that data is current and efficiently stored. Also, you do not need to maintain two sets of the same data.
When deciding to create a view or a new table, consider these questions:
Do you want to index columns that are not indexed in the source table?
Create a table because you cannot index columns in a view. See Creating Indexes.
Do you want to index columns that contain data you need to transform?
Many data sources ignore indexes on columns with transformations. You probably need to create a new table. See Transforming Data.
Create tables and views in the staging area. See Deciding to Create Staging Areas.