A foreign Key attribute

A foreign Key attribute is:

• a)An attribute, which is part of the key

• b)An attribute that references the primary key of another relation

• c) A composite attribute

• d) An attribute, which is not part of the key

The generalization process in an EER model is:

• a)A bottom up approach


• b)The process of defining super classes of entity types


• c) The process of defining an entity type that contains the common features of a set of entity types

• d) All of the above

First normal form (1NF) resolves anomalies caused by:

• a) Transitive dependencies

• b) Multivalued attributes and/or repeating groups

• c) Partial dependency on the primary key

• d) All of the above

A prime attribute is an attribute that: all of above

• a) can always Identify a relation

• b) must functionally determine another attribute

• c) is part of the key of a relation

• d) all of the above

A none- prime attribute is an attribute that: all of above

• a) can always Identify a relation

• b) must functionally determine another attribute

• c) is not part of the key of a relation

• d) all of the above

The purpose of normalization is:

• a) To optimize data-retrieval performance

• b) To optimize data for inserts, updates, and deletes

• c) To eliminate redundant data

• d) To remove certain anomalies from the relations

Which of the following is true about a key attribute A in relation R?

• a) A functionally determines all the attributes in R

• b) The values of A in the instance of R are unique for every tuple in R

• c) A must include more than one prime attribute

• d) All of the above

Consider the following database for the following question: course (c_id, title, semester, year) instructor (I_ id, name, nationality) teach (courseld, instructorid) courseid in teach is a FK that references c_id in course. instructorid in teach is a FK that reference i_id in instructor Identify the SQL command, which will return the title of all courses taught by "Abdullah" in "Spring 2019”

• a) SELECT title FROM course, teach, instructor WHERE courseid = c_id AND name= "Abdulla"

• b) SELECT title FROM course, instructor WHERE name = "Abdulla" AND year = 2019 AND semester = "Spring"

• c) SELECT title FROM course, teach, instructor WHERE coursed = c_id AND instructorid = i_id AND name= "Abdulla" AND semester = "Spring" AND year = 2019

• d) SELECT title FROM course, teach, instructor WHERE courscid = c_id AND instructorid = i_id AND course.year = teach.year AND name = "Abdulla" AND semester = "Spring" AND year = 2019

A key constraint:

• a) Must have primary key and foreign key columns that have identical names

• b) Ensures that a primary key does not have duplicate values in a relation

• c) Defines a many-to-many relationship between two relations

• d) Ensures that a foreign key value always refers to an existing primary key value in another relation

A correlated nested query is a query that:

• a) Must have two or more different relations involved in the query

• b) Has an inner query that is independent of the result of the outer query

• c) Has a query that is embedded within an outer query and depends on it

• d) None of the above