Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

First Sem-2nd Year > Databases-chap 1 > Flashcards

Databases-chap 1 Flashcards

1
Q

Who is Colossus

A

The world’s first electronic, digital, programmable computer used by British code breakers to help read encrypted German messages during WW2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Data vs Information

A

Data: Raw facts, must be properly formatted for storage, processing and presentation
Information: Data processed to reveal meaning needs to be in context to reveal meaning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Pyramid

A

Knowledge: Body of information and facts about a specific subject
Information
Data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Data quality aspects

A

Accuracy
Relevance
Completeness
Timeliness
Uniqueness vs redundancy
Unambiguous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Data management

A

Discipline that focuses on the proper generation, storage and retrieval of data
Core activity of any business, gov agency, service org or charity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Data governance

A

Describes a strategy or methodology defined by an org to safeguard data quality
Policies and procedures to manage availability, usability, quality, integrity and security of data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does DBMS do?

A

Manages the interaction between end user and the database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Database

A

Shared, integrated computer structure that stores
End user data(raw facts)
Metadata(data about data)
Name of each data element
Types of values(numeric, dates or text)-Data type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

DBMS

A

Collection of programs that manages database structure and controls access to data
Intermediary between the user and database
Possible to share data among multiple applications or users
Makes data management more efficient and effective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Roles and advantages of the DBMS(notes)

A
  1. Improved data sharing – enables quick responses
  2. Improved data security – enforce policies
  3. Better data integration – see organization as a whole
  4. Minimized data inconsistency – different versions of data
  5. Improved data access – use of queries
  6. Improved decision making – can be competitive
  7. Increased end-user productivity – empowers employees
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Disadvantages of DBMS

A

1.Increased cost
– Hardware, software, staff, training, licensing
2.Management complexity
3.Maintain currency
4. Vendor dependence
5.Frequent upgrade/replacement cycles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Types of databases

A
  • Classified according to:
    – Number of users supported
    – Where the data is located
    – Type of data stored
    – Intended data usage
    – Degree to which data is structured
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Number of users supported

A

Single user
Multi-user
Workgroup
Enterprise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Location

A

Centralized:Supports data located at a single site
Distributed:Supports data distributed across several sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Type of data stored

A

General purpose databases
– Wide variety of data used in multiple disciplines e.g. google
Discipline-specific databases
– Data focused on specific subject area e.g. medical or academic database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Internal data usage

A

Operational database
– Day to day operations e.g. sales
Analytical databases
– Storing historical data used for tactical or strategic decision making

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Degree of data structuring

A

Unstructured data
– Exist in format it was collected
– Difficult to turn into information
* Structured data
– Formatted unstructured data to facilitate storage and use

18
Q

Why is database design important

A

Poorly designed database generates errors>leads to bad decisions>can lead to failure of the org

19
Q

Problems with File System
Data Processing

A
  • Lengthy development times
  • Difficulty of getting quick answers
  • Complex system administration
  • Lack of security and limited data sharing
  • Extensive programming
20
Q

Evolution of file systems

A

Manual file systems
* Paper and pencil systems
– Organized to facilitate the expected use of data
– Amount of data needs to be small
– Few reporting requirements

Computerized file systems
* Make use of a data processing specialist
– Each query needed a new program to be written
– Initially files were created to be similar to manual files
e.g. add to, update and delete data from files
– Time consuming from query to final report

21
Q

Structural dependence

A

– Access to a file depends on its structure
– To add one field in a file system requires many changes
– None of the previous programs will work and must be
modified to confirm to the new file structure

22
Q

Structural independence

A

Change the file structure without affecting the
applications ability to access the data

23
Q

Data dependence

A

Is where data storage characteristics cannot be changed easily

24
Q

Data independence

A

Changes in the data storage characteristics without affecting the application program’s ability to access the data

25
Data redundancy(types of data anomalies)
* Update anomalies – Occur when changes must be made to existing records * Insertion anomalies – Occur when entering new records * Deletion anomalies – Occur when deleting records
26
Data redundancy(outcome)
– Poor data security * Multiple copies ‘floating around’ – Data inconsistency * Different and conflicting versions of the same data appear in different places – Data anomalies * Not all of the required changes are made successfully
27
The Database System Environment
Hardware * Physical devices, storage devices, printers, network devices – Software * Operating system software e.g. Windows * DBMS software e.g. SQL, Oracle * Application programs and utility software e.g. generate reports – People * E.g. system administrators, database designers, system analysts, end user – Procedures * Instructions and rules that govern the design and use of database system – Data
28
DBMS functions
Data dictionary management * defines data elements and their relationships – Data storage management * stores data and related data entry forms, report definitions
29
DBMS functions
Data transformation and presentation * translates logical requests into commands to physically locate and retrieve the requested data – Security management * enforces user security and data privacy within database
30
DBMS functions
-Multiuser access control * uses sophisticated algorithms to ensure multiple users can access the database concurrently without compromising the integrity of the database – Backup and recovery management * provides backup and data recovery procedures – Data integrity management * Integrates the many different users' views of data into a single all encompassing data repository
31
DBMS functions
Database access languages and application programming interfaces * provide data access through a query language e.g. SQL – Database communication interfaces * allow database to accept end-user requests via multiple, different network environments
32
Knowledge
The body of information and facts about a specific subject
33
Database design
Refers to the activities that focus on the design of the database structure that will be used to store and manage end-user data
34
Field
A character/group of characters that has a specific meaning. A field is used to define and store data
35
Record
A logically connected set of one or more fields that describes a person, place or thing
36
File
A collection of related records
37
Data warehouse
Focuses primarily on storing data used to generate information required to make tactical/strategic decisions(require extensive data manipulation)
38
Method of the file system purposes
-Understanding the shortcoming of the file system enables you to understand the development of modern databases -Many of the problems are not unique to file systems. Can lead to duplication in a database environment.
39
Limitations of file system data management
Requires extensive programming There are no ad hoc query capabilities System admin can be complex and difficult It is difficult to make changes to existing structures Security features are likely to be inadequate
40
When does data anomaly develop?
When all of the required changes in the redundant data are not made successfully
41
Database system
To an organization of components that define and regulate the collection, storage, management and use of data within a database environment

First Sem-2nd Year (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions