Views and Updateability in Relational Database Systems

This set of flashcards covers key terms and concepts related to views and updateability in relational database systems, focusing on their definitions and functionalities.

View

A named query that functions as a virtual table derived from base tables.

SQL Views

Used to organize relational data for access in main memory across applications.

Logical Independence

The ability to change the logical schema without changing the external schema.

Materialized View

A view that physically stores the result set on disk to avoid re-computation.

Updateability

The property of a view that allows it to be updated, reflected in the underlying base tables.

Aggregate Function

A function that summarizes a set of values (e.g., avg, count), often resulting in non-updateable views.

Authorization

The permissions granted to users determining what they can do with data.

Virtual Table

A table created as a view that does not exist physically in the database.

Three-Schema Architecture

A framework that describes the structure of a database system with external, conceptual, and internal levels.

Query Modification

The process of transforming view queries into corresponding queries on base tables.

Base Tables

The underlying tables from which views are derived.

Roles

Groups of users with the same data access privileges for managing authorization.

View Maintenance

The process of keeping views updated according to the changes in the base tables.