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Virtual DataPort allows users to connect to different data sources. Once the connection is established, views can then be created on top of the data sources. These views are called base views.

A developer can use base views to define new relations, which are called derived views. Derived views may appear in the FROM clause of any VQL query and can be used as a base for constructing new views or queries.

It is important to keep in mind that although derived views can be used as a base for new relations, Virtual DataPort uses different syntaxes for base views and derived views:

  • CREATE/ALTER/DROP TABLE base_view_name
  • CREATE/ALTER/DROP VIEW derived_view_name

If the above syntaxes are used incorrectly, (e.g. trying to modify a derived view with the ALTER TABLE command), Virtual DataPort will throw a “Selected view is not a base view” error.

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