Question 4

Question 1

Think of different users for the database of Figure 1.2. What type of applications would each user need? To which user category would each belong and what type of interface would they need? (a)

Answer 1

Registration Office User: They can enter data that reflect the registration of students in sections of courses, and later enter the grades of the students. Applications can include:
-Register a student in a section of a course
-Check whether a student who is registered in a course has the appropriate prerequisite courses
-Drop a student from a section of a course
-Add a student to a section of a course
-Enter the student grades for a section
Application programmers can write a number of canned transactions for the registration office end-users, providing them with either forms and menus, or with a parametric interface.

Question 2

Think of different users for the database of Figure 1.2. What type of applications would each user need? To which user category would each belong and what type of interface would they need? (b)

Answer 2

Admissions Office User: The main application is to enter newly accepted students into the database. Can use the same type of interfaces as (a).

Question 3

Think of different users for the database of Figure 1.2. What type of applications would each user need? To which user category would each belong and what type of interface would they need? (c)

Answer 3

Transcripts Office User: The main application is to print student transcripts.
Application programmers can write a canned transaction using a report generator utility to print the transcript of a student in a prescribed format. The particular student can be identified by name or social security number. Another application would be to generate grade slips at the end of each semester for all students who have completed courses during that semester. Again, this application could be programmed using a report generator utility

Question 4

Consider Figure 2.1. In addition to constraints relating the values of columns in one table to columns in another table, there are also constraints that impose restrictions on values in a column or a combination of columns within a table. One such constraint forces that a column or a group of columns must be unique across all rows in the table.
For example, in the STUDENT table, the StudentNumber column must be unique (to prevent two different students from having the same StudentNumber). Identify the column or the group of columns in the other tables that must be unique across all rows in the table? (a)

Answer 4

Table: COURSE
Column(s): CourseNumber
Since this contains the combination of the department and the number that must be unique within the department. Note we will overlook the fact this does not accommodate a department from offering several “Special Topics” course with the same CourseNumber but different titles. We could make this a combination of CourseNumber and CourseName, but this is more succeptible to someone mistyping while entering data.

Question 5

Consider Figure 2.1. In addition to constraints relating the values of columns in one table to columns in another table, there are also constraints that impose restrictions on values in a column or a combination of columns within a table. One such constraint forces that a column or a group of columns must be unique across all rows in the table.
For example, in the STUDENT table, the StudentNumber column must be unique (to prevent two different students from having the same StudentNumber). Identify the column or the group of columns in the other tables that must be unique across all rows in the table? (b)

Answer 5

Table: PREREQUISITE

Column(s): The combination of CourseNumber and PrerequisiteNumber

Question 6

Consider Figure 2.1. In addition to constraints relating the values of columns in one table to columns in another table, there are also constraints that impose restrictions on values in a column or a combination of columns within a table. One such constraint forces that a column or a group of columns must be unique across all rows in the table.
For example, in the STUDENT table, the StudentNumber column must be unique (to prevent two different students from having the same StudentNumber). Identify the column or the group of columns in the other tables that must be unique across all rows in the table? (c)

Answer 6

Table: SECTION
Column(s): SectionIdentifier
We assume that no two sections can have the same SectionIdentifier. If we were to consider that SectionIdentifier is unique only within a given course offered in a given term (such as section 2 of CS101) then the answer changes to the combination of SectionIdentifier, CourseNumber, Semester, and Year

Question 7

Consider Figure 2.1. In addition to constraints relating the values of columns in one table to columns in another table, there are also constraints that impose restrictions on values in a column or a combination of columns within a table. One such constraint forces that a column or a group of columns must be unique across all rows in the table.
For example, in the STUDENT table, the StudentNumber column must be unique (to prevent two different students from having the same StudentNumber). Identify the column or the group of columns in the other tables that must be unique across all rows in the table? (d)

Answer 7

Table: GRADE_REPORT
Column(s): StudentNumber and SectionIdentifier
As per assumption stated in SECTION, the SectionIdentifier will be different if a student takes the same course or a different course in another term.