CS403 Midterm Solved MCQs with References by Moaaz

CS403- Database Management Systems · Solved MCQS · From Midterm Papers · April 29,2012 · PSMD01 · CS403- Database Management Systems

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) (Page 62)

Correct answer: sub-processes (which explain and decomposed the major process into small processes) (Page 62)

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. Constraint is a rule that restricts the values in a database. (Page 18)

Correct answer: Constraint is a rule that restricts the values in a database. (Page 18)

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

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

Which of the following constraints enforces entity integrity?

1. PRIMARY KEY
2. FOREIGN KEY
3. CHECK
4. NOT NULL (Page 134)

Correct answer: NOT NULL (Page 134)

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.

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

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

Controlling redundancy in a database management system DOES NOT help to

1. avoid duplication (Page 16)
2. avoid unnecessary wastage of storage space
3. avoid inconsistency among data

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.

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 (Page 26)
4. Allocation of storage locations and data structures

Correct answer: Communicating with database users (Page 26)

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. (Page 33)
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.

Correct answer: The conceptual level is a level of indication between the internal level and the external level. (Page 33)

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.
2. using a junction table with the keys from both the tables forming the composite primary key of the junction table.
3. by splitting each table into three
4. as a single table and rarely as two tables with primary and foreign key relationships.

Correct answer: by splitting the data into two tables with primary key and foreign key relationships.

Which of the following is not a benefit of normalization?

1. Minimize insertion anomolies
2. Minimize deletion anomolies
3. Minimize updation anomolies
4. Maximize redundancy (Page 162)

Correct answer: Maximize redundancy (Page 162)