Transcript บทที่ 6 ฐานข้อมูลและการสืบ

Contents
Basic knowledge on database and
searching
Electronic database for searching
Searching techniques
Retrieval in the future
1. Definition of database and retrieval
 “Database” is the collection of related information on the same
topic for convenient use. It uses a program to categorize
characteristics of information, facilitate saving information in
the database, update and search for information and designate
rights to use the database so that users can get access to the
information easily and effectively. It acts as the
media between database users to communicate
with each other.
For examples, to get access to Suan Dusit
Rajabhat University’s registration database
http://webregis.dusit.ac.th, users must have their
own account or username and a password to log
in with, in order to use services as the ISP
designates.
Searching is to systematically retrieve information from
various sources by using information technology to get
access to information conveniently and quickly
according to the user’s needs. Information can be
searched from sentences, characters or letters, pictures,
human voices, music sounds, songs and videos.
2. Components of Database
2.1 Hardware
2.2 Software
2.3 Data
2.4 Procedures
2.5 People
2.5 People
Data Administrators
Database Administrators
Systems Analysts
Database Designers
Programmers
End-users
3. Information Retrieval Process
4. Benefits of Database
 Stored information becomes less
redundant.
 Stored information is up to date.
 Information can be shared.
 Information is protected
by the security system.
e-Journal
e-Book
e-Thesis or e-Research
Clipping
Information Resources Database of Information
Service Institute
e-Journal
http://arit.dusit.ac.th
e-Book
Other interesting E-book websites are those providing books and
journals concerning computer and computer program usage;
 Google books
(books.google.co.th)
 Computer Books and Article
(http://www.siamebook.com)
 Ramkamhaeng University’s Textbooks Center
(http://e-book.ram.edu/e-book/indexstart.htm)
 National Library’s electronic books
(http://www.nlt.go.th/data/ebooks/ebooks.html)
e-Thesis or e-Research
Clipping
Information Resources Database of
Information Service Institute
Table 6.4: Connectors or symbols used in searching information.
Connectors
/Symbols
Definitions
Examples
AND
Connect two words above. Both of the two words
occur in searching results.
Computer
AND Internet
OR
Connect two words above. One or both of the two
occur in searching results.
Computer OR
Internet
Connect two words above. Only the first word occurs
in searching results, the second one does not. (The
symbol – can be used instead of not.)
Computer
NOT Internet
NOT
Connectors/
Symbols
Definitions
Examples
?
The symbol “?” represents any letters. The word
will occur in search results, for example, int??net.
The results are internet, intranet….
The symbol is used to search unsure words or
groups of words with the symbol, “*”. It represents
any letters following the searched words. The
earched words are enclosed with a quotation mark,
for example, “int*”. The results are inter, internet,
international…
The symbol is used only for certain words defined.
The results will only show the particular words in
search results.
The symbol is used to search for synonyms with the
symbol, “~”. The results will show the words
having similar or close meaning.
The symbol “ ” is used to search for the words we
know exactly, for example, personal names, book
titles, song titles and place names etc.
Int??net
*
#
~
“”
“Inter*”
Program#
~food
“Prisna
Matchima”
 “Multimedia” is the mixture of various
kinds of media including texts, images,
animations, sounds and videos by using
computer processes to express meaning and
interact with users according to
their purposes.
There are various kinds of multimedia
services for users by searching
Pictures on the internet
Sounds on the internet
Videos on the internet
Image Retrieval
http://images.google.co.th
Sound Retrieval
http://music.yahoo.com
Video Retrieval
http://www.youtube.com
To enhance effective searching, in the era of web 3.0,
with information connected more than before by a
semantic network, some more intelligent programs
such as intelligent agents and semantic searches
are developed.