These are questions about database management systems. 1. Match the following te
ID: 3687406 • Letter: T
Question
These are questions about database management systems.
1. Match the following terms with the correct definition. Each term is used only once.
Entity, attribute, record, field
A. Object in our environment we want to keep track of
B .Each row of a table
C. Each column of a table
D. Property or characteristic of an object we want to keep track of
2. Data integration is:
A. When we store the same fact about the business environment more than once with an information.
B. Having timely and accurate data
C. The ability to the together pieces of related data within an information system
D. Removal of all anomalies in the data
3. In a relational database, the basic structure that data is stored in is a:
A. File
B. Column
C. Row
D. attribute
E. table
4. A foreign key does have to have unique values in the relation in which it is a foreign key
A. True
B. False
5. The storage media that is a plastic disk read by a laser is known as:
A. solid state technology
B .punched paper cards
C. compact disks
D. magnetic drums
6. The cardinality of a relationship is ___.
A. The maximum number of entity instances that can be involved in the relationship.
B. The minimum number of associations that can be involved in the relationship.
C. The maximum number of attributes that can be in the entity types in a relationship
D. The minimum number of attributes that can be in the entity types in a relationship
E. The minimum number of entity instances that can be involved in the relationship.
7. In a correctly designed table in a relation database which of the following is true?
A. No two rows are identical
B. the columns must be arranged in a single, particular order
C. Several rows can be identical
D. The rows must be arranged in a single particular order
E.A single row/column position called a cell, can have multiple values
8. A one to one binary relationship___
A. Involves a single entity type
B. allows an occurrence of one entity type to be associated with several occurrences of another entity type
C. restricts the number of attributes that an entity has
D. involves two entity types
9. Match each term with its definition or associated technology or inventor
each term is used only once
(earliest form of modern data storage, Blaise Pacal, Joseph Marie Jacquard, world’s first electronic computer, Herman Hollerith, data storage used by business in the 1950’s )
A. punched paper tape
B. punched cards
C.ENIAC
D .tabulating machine
E. magnetic disk
10. Representing a unary many-to-many relationship in a relation database__.
A. requires adding a new attribute to the original entity, the domain of values of which is the same as the primary key of another entity in the database
B. requires replacing the primary key of the entity with an alternate key
C. requires the creation of an additional entity
D. requires modifying the primary key of the entity
11. O map a one-to many relationship an ERD to relations in logical design, you:
A. make an new entity in the middle that includes the primary keys of both the original entities
B. put the primary key of the entity on the many side in entity on the one side as foreign key
C. put the primary key of the entity on the one side in entity on many side as a foreign key
12. the values of the primary key of a relation____
A. may be unique or non-unique
B. cannot be unique
C. must be unique
D. must consist of a single attribute
13. In a university setting, every professor reports to another professor who is the department chairperson. It is possible for two professors to have the same chairperson. This is a ___ relationship
A.one-to-one-binary
B.many-to-many-binary
C.One-to-many-unary
D.one-to-one-unary
E.one-to-many unary
14. he entity-relationship(E-R) model is__
A.an alternative to file design in which attributes are used instead of fields
B.an alternative to indexing and hashing as a means for providing direct access in files
C. a diagramming technique that describes entities their attributes, and the relationships between the entities
D. a diagramming technique that describes record structures(ie. The fields that make up the records a file)
E. a diagramming technique that relates entities to each other, attributes to each other, and relationships to each other
15. An association between entities is an____
A. record
B. Relationship
C. entity type
D. entity instance
E. attribute
16. A foreign key is always the primary key of another entity.
A. True
B.False
Explanation / Answer
Answer
------
1.
A - Entities
B - Record
C - Field
D - Attribute
2. B
Data integration involves combining data residing in different sources and providing users with a unified view of these data.It is used basically to maintain accurate data.
3. E
4. B
Foreign key no need to maintain unique values in the relation(table) in which it is used as foreign key.Only primary key needs to be unique.
For ex:- If student(stid,stname,grpid), college groups(grpid,grpname) are two different tables and grpid is foreign key in the student table then many students can access same college group
5. C - compact disks
6.A. The maximum number of entity instances that can be involved in the relationship.
7.A. No two rows are identical
8.D. involves two entity types
9.
A. punched paper tape -
B. punched cards -
C.ENIAC - world’s first electronic computer
D .tabulating machine - Herman Hollerith
E. magnetic disk -
10.
11.
12.C. must be unique
13.E.one-to-many unary
14.C. a diagramming technique that describes entities their attributes, and the relationships between the entities
15.B. Relationship
16. True
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.