1.1: Traditional File Management vs Database Management

Question 1

Problems Of Early Data Processing

Answer 1

Redundancy, Inconsistency, Data-program dependence, Inflexibility

Question 2

Data-program dependence (early data processing)

Answer 2

Strict data gathering by the application program, changes in data structure, will require changes in the program.

Question 3

Redundancy (early data processing)

Answer 3

Repeated data, wasted memory, etc.

Question 4

Inconsistency (early data processing)

Answer 4

Errors between data sets, since one can be updated by not another.

Question 5

Inflexibility (early data processing)

Answer 5

Problematic to analyze data, since there’s several files that must have to be combined with high costs

Question 6

Advantages of Database Systems

Answer 6

Data Independence, Efficient data access, Common data basis, Concurrent data access, Lacking or Controlled Redundancy, Consistency of Data, Integrity of Data

Question 7

Data Independence (database systems)

Answer 7

Independent of application programs, no need to update program when data structure changes.

Question 8

Efficient data access (database systems)

Answer 8

Index structures (allows quick access)

Question 9

Common data basis (database systems)

Answer 9

since data is not repeated, it is updated correctly in the database. (avoids mismatch of data)

Question 10

Concurrent data access (database systems)

Answer 10

Allows multiple users to access data. Concept of transaction for the synchronization of concurrent data accesses.

Question 11

Lacking or Controlled Redundancy (database system)

Answer 11

avoids copies of same data, or controlled redundancy to improve performance.

Question 12

Consistency of data (database system)

Answer 12

lacking redundancy, DBMS ensures consistency of data for controlled redundancy

Question 13

INTEGRITY of data (database system)

Answer 13

Correctness and completeness of data. Formulation of integrity constraints or integrity rules. DBMS checks constraints for each insertion, change, and deletion of data

Question 14

SECURITY of Data (database system)

Answer 14

Protection of unauthorized access (view on data). Access control, authentication and encoding are possible protection mechanisms.

Question 15

Backup and Recovery (database system)

Answer 15

backup - copies of external storage media (e.g. tapes, discs)
recovery - automatic reconstruction of the last, up-to-date, and consistent database status with aids of tapes and listing the executed changes.

Question 16

Posing QUERIES (database system)

Answer 16

Query language, allows, to pose queries to get an immediate answer
Queries can be pose ad hoc (keyboard), embedded into database application programs. Importance of query optimization, query processing, and query execution.

Question 17

Provision of diversified USER INTERFACES (database system)

Answer 17

query languages for occasional users, programming interfaces for implementers, etc.

Question 18

Database (DB)

Answer 18

Structured storage of large collections of persistent data, reliable basis of up-to-date information.

Question 19

Database Management System (DBMS)

Answer 19

All-purpose software system. Allows user to build and manipulate databases in an efficient manner. Software level between physical database and user.

Question 20

Database System (DBS)

Answer 20

DBS = DBMS + DB
The Database Management System in addition of Database

Question 21

Meta Data (Stored database definitions)

Answer 21

Data about the data. ex. For a student we will store (first name, last name, DOB, etc)
Structure of a database

Question 22

Raw Data (Stored database definitions)

Answer 22

The actual data. (Carlos, 18, Student)

Question 23

Data Model

Answer 23

Description of structure of a database (data types, relationships, conditions) alongside operations for handling and manipulating the data.

Question 24

Data Model Offers:

Answer 24

specs of data objects
specs of relationships between data
specs of operations on data objects

Question 25

DBS has at least 2 data models:

Answer 25

Physical, and Logical (data models)

Question 26

Physical data model

Answer 26

storage-oriented representation of data.

Question 27

Logical data model

Answer 27

user-oriented representation of data.

Question 28

Types of Logical data models

Answer 28

Object-based & Record-based

Question 29

Name 3 object based (logical) models

Answer 29

Entity-Relationship Model Object-Oriented Data Model Object-Relational Data Model (object & record)

Question 30

Name 4 record-based (logical) models

Answer 30

Object-Relational Model (object & record) Relational Data Model Network Data Model Hierarchical data model

Question 31

Select all disadvantages of file systems found in the following list: * Inflexibility * Redundancy * Data-program independence * Consistency

Answer 31

Inflexibility Redundancy

Question 32

Select all ADVANTAGES of database systems found in the following list: * Efficient data access * Concurrent data access * Data independence * Integrity of data * Common data basis

Answer 32

* Efficient data access * Concurrent data access * Data independence * Integrity of data * Common data basis

Question 33

A data definition language allows the user to: A) Define and change the structure of a database. B) Design the structure of a database. C) No answer text provided. D) Manipulate the data in a database.

Answer 33

A) Define and change the structure of a database.

Question 34

A query allows the user to pose ad hoc queries by using the keyboard and get an immediate answer (True or False)

Answer 34

TRUE

Question 35

Which statements are correct? A database management system is: * A set of programs for the management of and access to the data in the database. * An all-purpose software system, which supports the user in the definition, construction and manipulation of databases for different applications in an application-neutral and efficient manner. * A hardware level between the physical database and the user. * A repository of data.

Answer 35

* A set of programs for the management of and access to the data in the database. * An all-purpose software system, which supports the user in the definition, construction and manipulation of databases for different applications in an application-neutral and efficient manner.

Question 36

Which statements are correct? Metadata: * Mean "data about data" * Describe the operations of a database system. * Are data about the definition of the structure of a database.

Answer 36

* Mean "data about data" * Are data about the definition of the structure of a database.

Question 37

The user-oriented representation of data is provided by the: A) Logical Data Model B) Physical Data Model

Answer 37

A) Logical Data Model

Question 38

What type of data model is a relational data model?

Answer 38

A record-based data model