CS403 Midterm Solved Paper 2010 Session 2

MIDTERM · EXAMINATION · Spring 2010 · CS403- Database Management Systems (Session - 2)

Q1. ( M a r k s: 1 )

Which of the following is NOT a feature of Context DFD?

1. one process (which represents the entire system)
2. all sources/sinks (external entities)
3. data flows linking the process to the sources and sinks (external entities)
4. sub-processes (which explain and decomposed the major process into small processes)

Q2. ( M a r k s: 1 )

Which of the following is true for the relational model?

1. Degree of a relation is the number of rows in a relation.
2. 
3. Null value is a blank or zero value given to an attribute value when its value is inapplicable or its value is unknown.
4. 
5. Complex key is a key consisting of more than one attribute.
6. 
7. 
8. Constraint is a rule that restricts the values in a database.

Correct answer: Constraint is a rule that restricts the values in a database.

Q3. ( M a r k s: 1 )

Which one of the following four E-R diagrams is the typical result you obtain when you initially start with an E-R diagram containing just two entities, A and C, in a Many-to-Many relationship, and then introduce an associative entity (B).

Q4. ( M a r k s: 1 )

Which of the following most certainly implies the need for an entire table to implement?

1. A binary relationship
2. A ternary relationship
3. A recursive relationship
4. An identifying relationship

Correct answer: A ternary relationship

Q5. ( M a r k s: 1 )

Which of the following constraints enforces entity integrity?

1. PRIMARY KEY
2. FOREIGN KEY
3. CHECK
4. NOT NULL

Correct answer: PRIMARY KEY

let see few types of constraints Entity Integrity ensures that there are no duplicate rows in a table. Domain Integrity enforces valid entries for a given column by restricting the type, the format, or the range of possible values. Referential integrity ensures that rows cannot be deleted, which are used by other records (for example, corresponding data values between tables will be vital). User-Defined Integrity enforces some specific business rules that do not fall into entity, domain, or referential integrity categories.

Q6. ( M a r k s: 1 )

Which of the following is not true about relational tables?

1. Column values are of the same kind.
2. Each row is unique.
3. Each column must have a unique name.
4. The sequence of rows is significant.

Correct answer: The sequence of rows is significant.

Q7. ( M a r k s: 1 )

In a conceptual model for a university, what type of relationship exists between Grade and Student entities?

1. 1:1
2. 1:M
3. M:M
4. Ternary

Q8. ( M a r k s: 1 )

Controlling redundancy in a database management system DOES NOT help to

1. avoid duplication
2. avoid unnecessary wastage of storage space
3. avoid unauthorised access to data
4. avoid inconsistency among data

Correct answer: avoid unauthorised access to data

Q9. ( M a r k s: 1 )

Which of the following is INCORRECT with respect to file systems?

1. At the physical level, pointer or hashed address scheme may be employed to provide a certain degree of data independence at the user level.
2. A logical record is concerned with efficient storage of information in the secondary storage devices.
3. Some physical organisations use pointers to record blocks to locate records on disk.
4. The efficiency of a file system depends on how efficiently operations such as retrieve, insert, update, delete may be performed on the information stored in the file.

Q10. Which of the following functions are NOT performed by a database administrator?

1. Planning, designing and implementing database systems
2. Establishing standards and procedures for database systems
3. Communicating with database users
4. Allocation of storage locations and data structures

Q11. ( M a r k s: 1 )

Select the correct statement about the ANSI/SPARC architecture.

1. The conceptual level is a level of indication between the internal level and the external level.
2. The internal level in a database system will definitely be relational.
3. Any given database has many conceptual schemas and one physical schema, but it has only one external schemas.
4. The external level is not concerned with individual user perceptions, while the conceptual level is concerned with a community user perception.

Q12. ( M a r k s: 1 )

Which of the following is a correct way to implement one-to-many relationship while designing tables?

1. by splitting the data into two tables with primary key and

foreign key relationships.

1. using a junction table with the keys from both the tables

forming the composite primary key of the junction table.

1. by splitting each table into three
2. as a single table and rarely as two tables with primary

and foreign key relationships.

Q13. Which of the following is not a benefit of normalization?

1. Minimize insertion anomolies
2. Minimize deletion anomolies