Database Systems Concepts & Architecture

Question 1

Data Model

Answer 1

Collection of cncepta that’s describe the STRUCTURE, of the database and CONSTRAINTS that apply to the data and include operations for manipulating the structures l

Question 2

Conceptual data models

Answer 2

Concepts that are close to the way users perceive the data

Question 3

Entity

Answer 3

A real-works object or concepts

Question 4

Attribute

Answer 4

Represents some property describing an Entity

Question 5

Relationship

Answer 5

An association between two entities

Question 6

Physical data models

Answer 6

Concepts that describe the details of how data is stored

Question 7

Self describing data model

Answer 7

Combines the data description with the data values in the storage

Question 8

Schema (intension)

Answer 8

Includes a description of the database structure, data types, and the constrains on the database

Question 9

Schema Construct

Answer 9

A component of the schema or an object within schema e.g. STUDENT

Question 10

DDL used for what schemas?

Answer 10

1. Conceptual schema with no clear separation between internal and conceptual
2. Define conceptual and internal schema with no strict separation of levels

Question 11

VDL is used for?

Answer 11

Specifying the user views and Their mapping to the conceptual schema

Question 12

SQL used in what language?

Answer 12

VDL in relational DBMS to define user or application views

Question 13

DML is?

Answer 13

Data manipulation language (Creat, Read, Update, Delete) CRUD

Question 14

Database system utilities

Answer 14

Loading data, backing up database, reorganize, report generation utilities, performance monitoring

Question 15

3 schema architecture

Answer 15

Self describing, insulation of programs and data, multi-user support

Question 16

3 levels of data description

Answer 16

External, conceptual, internal

Question 17

Logical Data independence

Answer 17

Ability to change conceptual schema without having to change external schemas or application programs

Question 18

Conceptual schema

Answer 18

Describes the database structure

Question 19

Physical Data Independence

Answer 19

Ability to change the internal schema without having to change the conceptual schema