MMIS671 Constrained Optimization Problems Assignment Sample

• Internal Code :
• Subject Code : MMIS671
• University :
• Subject Name : Business Intelligence

Fundamental Analytics and Business Intelligence

1. Explain the concept of physical data independence and its importance in database systems

Data independence described as the property of database management system that helps the user in changing the schema of database at one level of the database system without need to change the schema at next and higher level. Data independence help in keeping the data separated from all different programs that make use out of it. In Database management system, there are two types of data independence. First is logical data independence and second is physical data independence.

Physical data independence helps the user in separating the internal or physical level from the conceptual level. It permits the user to offer a logical description of the database and there is no need to specify the physical structure if the data base. If compare both the logical dependence then it easy to accomplish physical data independence.

With the help of physical data independence, user can transform the physical structure of storage easily and also change the physical device easily with an impact on the conceptual schema. Any change can execute with the help of mapping among internal and conceptual levels. IT can be accomplished with the help of internal level of database and then change from the conceptual to the internal level of database.

Physical data independence is achieved by the presence of the internal level of the database and then the transformation from the conceptual level of the database to the internal level.

2. There is various problem in the table, the customer id is same for two customers and there is no primary key in table, the user cannot identify the individual customer with the help of customer id. The customer id should be unique in the table. If the customer id is unique then it is known as primary key. Primary key is unique and it is used to identify different customers with the help of customer id. The name of two customers can be same but the customer id should be unique to identify the different customer.

A primary key is used to access the record of the customers from the table. If there is no primary key in the table then the table leads to computation artifacts.

Primary key is the basic aspect to create a table. 

3. List four significant differences between a file-processing system and a DBMS.

File processing system	Database Management System
The problem of redundancy cannot be controlled in the file system	The issue of redundancy can be controlled in Database management system.
A file system offers loose guarantee of various problems like consistency, durability and isolation.	Database is very much consistent all the time, it provides durable writes and
The file processing system can only coordinate with the physical access of the database.	A database system provides coordination with both to access the data, the physical and logical access.
There is no restriction on the unauthorized access in DBMS	There is restriction on the unauthorized in DBMS

4. Describe the differences in meaning between the term’s relation and relation schema.

Relation

Relation schema

Relation is called table sometimes in the relational database but generally it is used to describe the relationship among tables used in the relational database. Every component in the relation is known as attribute value. It is the name of the value A relation is a table in the relational database because it used to store the relation among data in its row-column format. The columns are the relation’s attribute while data records are represented with the rows. Tuple is the single row to the database designers.

A relation schema is a set of attributes. It is also known as table schema. A relation schema is also used to represent the basic structure of the table and it also give the information about the table or relation. Relation schema is the definition but a logical one of the tables. It is also used to describe the name of the table. It also includes the number of column of tables, and the data type associated with each each attribute. Relational schema is also known as database schema. It is used to describe the prototype of database that used in a manner data is structured in the database.

5. List two reasons why null values might be introduced into the database.

Null is the special name used in SQL that is structured query language. It is used to indicate that the value of data does not exist in the database. The concept of Null value is introduced by the creator of relational database which is E.F.Codd.

Null is used to meet all the requirements of the RDBMS that is Relational database management system. It supports, “inapplicable information” and “missing information” to represent in database.

A null value shows the lack of value, it does not mean 0. Likewise, the lack of answer that does not mean the user don’t know the answer.

6. Find the titles of courses in the Comp. Sci department that have 4 credits.

SELECT titles of course

FROM Comp. Sci department

WHERE credits =4.

1. Find the name(s) of the instructor(s) who DON’T earn the lowest salary in Physics department.

SELECT instructor name

FROM Physics department

Where Salary > Lowest

2009. Find the enrollment of each section (number of students enrolled) that was offered in Fall 2009.

SELECT enrollment number

FROM student Table

WHERE enrollment number =Fall 2009

2009. Find the minimum enrollment, across all sections offered in Fall 2009.

SELECT min(enrollment)

From Section Table

2009. Find the course ID and section ID of the sections that had the minimum enrollment in Fall 2009.

SELECT course ID and Section ID

FROM section table

HAVING count (enrollment number) = minimum;

7. Find the names of all students who have taken at least two courses offered by Comp. Sci. department; make sure there are no duplicate names in the result. Note that student in other departments can take courses from Comp. Sci. as well.

SELECT DISTINCT Student names,

FROM Computer sci department

WHERE Courses >= 2;

b. Find the IDs and names of all students who have not taken any course offering in 2009.

SELECT IDs and student name

From Student table

GROUP BY IDs

HAVING =offering in 2009;

c. For each department, find the name and salary of the instructor who earns the minimum salary in that department. You may assume that every department has at least one instructor.

SELECT instructor salary

FROM Department Table

Where Salary =Minimum

ORDER BY SALARY DESC;

d. Find the highest, across all departments, of the per-department minimum salary computed by the preceding query.

SELECT instructor salary

FROM Department Table

Where Salary =Maximum

ORDER BY Salary;

e. Find the course titles of all prerequisite courses of “CS-319”.

SELECT course Title

FROM course table

HAVING prerequisite courses = “CS-319”;

Remember, at the center of any academic work, lies clarity and evidence. Should you need further assistance, do look up to our Business Intelligence Assignment Help