Three Schema Architecture

Question 1

It supports multiple views of data and promotes program-data independence

Answer 1

Three Schema Diagram

Question 2

A three schema architecture is not explicitly used in commercial DBMS products but has been useful in explaining database system organization

Answer 2

Three Schema Architecture

Question 3

This schema is at the internal level to describe physical storage structure and access paths. Typically uses a physical model

Answer 3

Internal Schema

Question 4

This schema is at the conceptual level to describe the structure of the whole database for a community of users. It uses a conceptual or an implementation data model

Answer 4

Conceptual Schema

Question 5

This schema is at the external level to describe various user views. It usually uses the same data model as the conceptual schema

Answer 5

External

Question 6

Mapping among schema levels are needed to transform requests and data.

Programs refer to an —– schema, and are mapped by the DBMS to the —— schema for execution

Answer 6

external
internal

Question 7

Data extracted from the —– DBMS level is reformatted to match the user’s external view.

Answer 7

internal

Question 8

This data independence has the capacity to change the conceptual schema without having to change the external schemas and their associated application programs.

Answer 8

Logical Data Independence

Question 9

This independence has the capacity to change the internal schema without having to change the conceptual schema.

Answer 9

Physical Data Independence

Question 10

Relational, Network, Hierarchical are an example of

Answer 10

Traditional

Question 11

Object oriented, Object-relational are an example of

Answer 11

emerging