Chapter 6

VIEWs, Derived, and Other Virtual Tables

Abstract

Unlike files and older database models, not all tables have a physical existence. Virtual tables are a major tool in SQL.

Keywords

Calculated column

CREATE VIEW

INSTEAD OF triggers

Materialized query tables

Nested VIEWs

Translated column

VIEW materialization

VIEW updating

WITH CHECK OPTION clause

WITH RECURSIVE clause

Views are also called virtual tables, to distinguish it from temporary and base tables which are persistent. Views and derived tables are the ways of putting a query into a named schema object. By that, I mean these things hold the query code rather than the results of the query. The query is executed and the results are effectively materialized as a table with the ...

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