If all you want is to perform an ad-hoc join, you can use the Database Query plugin (see http://www.tersus.com/#Id=3440) which can execute any valid select statement.
If on the other hand, what you need is to access a database View, note that as far as Tersus is concerned there is no distinction between a view and a table, and both are modeled as a Database Record. This means that while Tersus cannot create new views in the database, it has no problem accessing existing views.
Once a view is defined in the database (using the tools provided by the database itself), If your view (or table) is already defined in your database, there's no need to create it manually in Tersus. Instead you can use the Import Structure from Database wizard to import the definition (the wizard is available when right clicking a Database Record model).
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