Database Reference
In-Depth Information
COURSE
STUDENT
COURSE_PREREQUISITE
STUDENT_CLASS
10-30
CourseID
StudentID
CourseID (FK)
Prerequisite (FK)
ClassID (FK)
StudentID (FK)
Grade
FirstName
LastNme
CourseName
Credit
Description
P
P
0-7
Major
FacultyID (FK)
CLASS_CLASSROOM
P
CLASS
FACULT
P
BuildingID (FK)
ClassroomID (FK)
ClassID (FK)
CLASS_FACULTY
ClassID
CourseID (FK)
TimeID (FK)
SemesterID (FK)
DayID (FK)
FacultyID
FacultyID (FK)
ClassID (FK)
FirstName
LastName
Department
P
P
P
P
CLASSROOM
ClassroomID
BuildingID (FK)
Capacity
DAYS
DayID
TIMEBLOCK
SEMESTER
SemesterID
BUILDING
BuildingID
TimeID
P
We ekDay
TimeBlock
Semester
BuildingName
Figure 2.31
Data model for class registration process.
2.4 Database Physical Design
Before you can implement a database physically, careful consideration should be given on some
physical design issues. In your physical design, you need to specify the IT infrastructure that will
host the future database. For example, if you are designing a database for a company, you need to
ind out how the users can access the data stored in the database. If the users need to access your
database through a local area network or through the Internet, you need to carefully specify the
capacity and security of the network. At the physical design stage, you need to choose a server
that has enough room for adding more hard drives. It is risky to physically implement a database
without much thinking and hope everything will turn out alright. If something goes wrong, it is
too costly or too late for you to start all over again.
2.4.1 Database System Architecture
Before implementing a database, as a database designer, you need to know what type of system
architecture your future database will be built on. It is important to know if your database will
be hosted by a web-based system, a three-tier client-server system, or another type of system. For
example, if the database is network-based, you need to address the physical design issues such as the
capacity of the network, the security measures imposed on the network, the ability of the network
server to handle data transactions, Internet access facilities, and network-based storage and printing
equipment. To quickly identify physical implementation problems, let us categorize them below:
◾
Issues related to system architecture
◾
Issues related to data characteristics
◾
Issues related to database access
◾
Issues related to server and data storage equipment
