Introdaction to Python
Example for ER diagram
a
Example: design as (Figures and Tables) Entity Relationship diagram for a college?
We have the following statements:
1. A college contains many departments
2. Each department can offer any number of courses
3. Many instructors can work in a department
4. An instructor can work only in one department
5. For each department there is a Head
6. Each instructor can take any number of courses
7. A course can be taken by only one instructor
8. A student can enroll for any number of courses
9. Each course can have any number of students
Step 1: Identify the Entities
What are the entities here?
1. Department
2. Course
3. Instructor
4. Student
Stem 2: Identify the relationships
1. One department offers many courses. But one particular course can be
offered by only one department. hence the cardinality between department
and course is One to Many (1:M)
Example for ER diagram
a
Example: design as (Figures and Tables) Entity Relationship diagram for a college?
We have the following statements:
1. A college contains many departments
2. Each department can offer any number of courses
3. Many instructors can work in a department
4. An instructor can work only in one department
5. For each department there is a Head
6. Each instructor can take any number of courses
7. A course can be taken by only one instructor
8. A student can enroll for any number of courses
9. Each course can have any number of students
Step 1: Identify the Entities
What are the entities here?
1. Department
2. Course
3. Instructor
4. Student
Stem 2: Identify the relationships
1. One department offers many courses. But one particular course can be
offered by only one department. hence the cardinality between department
and course is One to Many (1:M)