Information Management - 1 Flashcards
1
Q
Database
A
- solve many of the problems encountered in data management
- Used in almost all modern settings involving data management
1. business
2. research
3. administration
2
Q
Data
A
- raw facts
- foundation of information and bedrock of knowledge
3
Q
information
A
- result of processed raw data to reveal its meaning
- requires context
4
Q
raw data
A
should be formatted for storage, preocessing, information
5
Q
Data
second definition
A
building blocks of information
6
Q
Information
second definition
A
- produced by processing data
- used to reveal meaning of data
7
Q
decision making
A
- accurate, timely, relevant key for good decision making
- key for organizational survival
8
Q
database
A
shared, integrated computer strcuture that collects: end-user and metadata
9
Q
end-user
A
raw facts that are in interest of end-user
10
Q
metadata
A
- data about data
- procide data characteristics
- complement and expand value of data
11
Q
database management system
(DBMS)
A
- collection of programs
- manages structure and controls access data
12
Q
role of dbms
A
- dbms serves as intermediary between user and database
- database structure stores file collection
- file collection can only be accessed through dbms
- dbms enables users to share data
- dbms integrates many users’ view of the data
13
Q
dbms interaction between enduser and database
A
https://player.slideplayer.com/89/14390402/slides/slide_4.jpg
14
Q
dbms advantages
A
- improved data sharing
- improved data security
- minimized data inconsistency
- improved data access
- improved decision making
- increased enduser productivity
14
Q
dbms advantages
A
- improved data sharing
- improved data security
- minimized data inconsistency
- improved data access
- improved decision making
- increased enduser productivity
15
Q
databasese can be classified
A
- number of users
- database location
- expected type and extent of use
16
Q
Single-user database
A
one user at a time
example: PC
17
Q
Multi-user database
A
caters multiple users at a single time
example: workgroup and enterprise
18
Q
centralized database
A
data located at a single location
19
Q
Distributed database
A
data distributed into several different sites
20
Q
Operational database
A
- company’s day-to-day operation
- transactional or production database
21
Q
Data warehouse
A
dta stored for tactical or strategical decisions
22
Q
Unstructured data
A
data in their original state
23
Q
Structured data
A
- data result from formatting
- structure applied based on type of processing to be performed
24
Semistructured data
have been processed to some extent
25
Extensible Markup Language
* data elements in a textual format
* **XML database** supports semistructured XML data
26
Types of database
1. Single-user database
2. Multi-user database
3. Centralized database
4. Distributed database
5. Operational Database
6. Data Warehouse
7. Unstructured data
8. Structured data
9. Semstructured data
10. Extensible Markup Language
27
database design
* focuses on the design of database structure for the end-user data
* designer must identify database expected use
27
Well-designed database
* facilitates data management
* generate accurate and valuable information
28
Poorly-designed database
causes difficult-to-trace errors
29
Reasons for studying system files
1. Complexity of database design makes its easier to understand
2. Understanding file system problems help aboid DBMS problem systems
3. Knowledge on file system makes it easier to convert file to database system
30
File system
* oraganized by their expected use
* collection of folders that are tagged and kept in a cabinet
31
Contents of folder are:
logically related
32
Manual Systems
* repository for small datasets
* cumbersome for large datasets
33
Computerized file systems
* **data processing specialist** converted computer file structure from manual system
* wrotethe software that managed the data
* designed the application programs
34
Initially, computer file sysetms resemebed
manual system
35
File
* collection of characters with specific meaning
* used to define ans store data
36
Record
logically connected set that is used to describe person or things
37
File
collection of related records
38
File system is an improvement over manual systems
* file systems used for more thna two decades
* understanding current shortcomings help aid in development of modern tech
* many problems not unique to file systems
39
Even simple retrieval task required extensive programming
* ad hoc queries is impossible
* changing structure is difficult
40
security features difficult to program
oftern omitted on system environment
41
Summary of file system limitations
1. requires extensive programming
2. cannot perfom ad hoc queries
3. system administration is complex and difficult
4. difficult to chnage existing structures
5. system security is likely inadequate
42
Problems with File System Data Processing
1. File system is an improvement more than manual system
2. Even simple file task retrieval needs extensive programming
3. Security features are difficult to program
43
Structural dependence
* access to a file is dependent on its own structure
* all programs should be modified to create new file structure
44
Structural independence
changes the file structure without affecting data access
45
Data dependence
data access changes when data strorage characteristics change
46
Data independence
data storage characteristics does not affect data access
47
Significance of data dependence
differencebetween phyical and logical format
48
Logical format
how human views the data
49
Physical format
how computer must work with data
50
Each program must contain
* specific line opening of a specific file type
* record specification
* field definition
51
Each program must contain
* specific line opening of a specific file type
* record specification
* field definition
52
Data redundancy
same data stored unnecessarily in different places
53
Data inconsistency
different conflicting versions of same data stored in different places
54
Data abnormalities
abnormalities occur in redundant data when changes does not occur correctly
* Update anomalies
* Insertion anomalies
* Deletion anomalies
55
Data modelling skills
are important in data design process
56
Good data modeling
57
Database Systems consists:
logically related data stored in logical data repository
* physical attributes are distributed
* DBMS eliminate file system's problems
* current generation stores data structures, relationship between structures, access paths
58
Database system
defines and regulates the collection, storage, management, use of data
59
Five major parts of a database system
1. HArdware
2. Software
3. Procedure
4. People
5. Data
60
hardware
computer's physical devices
61
software
* Operating system software
* DBMS software
* Application program and utility software
62
People
all users of the system
63
Procedure
tasks and rules given that govern the design and use of database system
64
Data
| majory part of system
the collection of facts stored in the database
65
Databse system
| last definition
are created and managed at different levels of complexity
66
Database Solutions
must be cost-effective as well as tactically and strategically effective
67
Databse Technology
technology already in use affects selection of a database system
68
DBMS Functions
**1. Most functions are transparent to end users**
* Can only be achieved through the DBMS
**2. Data dictionary management**
* DBMS stores definitions of data elements and relationships (metadata) in a data dictionary
* DBMS looks up required data component structures and relationships
* Changes automatically recorded in the dictionary
* DBMS provides data abstraction and removes structural and data dependency
**3. Data storage management**
* DBMS creates and manages complex structures required for data storage
* Also stores related data entry forms, screen definitions, report definitions, etc.
* ***Performance tuning:*** activities that make the database perform more efficiently
* DBMS stores the database in multiple physical data files
4. Data transformation and presentation
5. Security Management
6. Multiuser access control
7. Backup and recovery management
8. Data Integrity management
9. Database access language and programming interfaces
10. Database communication Interfaces
69
Query language
nonprocedural language
70
Structured Query Language
is the de facto query language
71
Managing the Database System: A Shift in Focus
* Database system provides a framework in which strict procedures and standards enforced
* Role of human changes from programming to managing organization’s resources
* Database system enables more sophisticated use of the data
* Data structures created within the database and their relationships determine effectiveness
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