1. Which of the following is not a characteristic of NoSQL databases?
A. Schema-less design
B. Horizontal scalability
C. Strong consistency
D. Non-relational data model
Answer: C
Rationale: NoSQL databases are often designed for horizontal scalability and
flexibility with a schema-less structure. They may favor eventual consistency over
strict consistency.
2. In the context of entity-relationship (ER) modeling, an entity is represented by:
A. A rectangle.
B. An oval.
C. A diamond.
D. A hexagon.
Answer: A
,Rationale: In ER modeling, entities are represented by rectangles, which symbolize
the objects or things in the real world that are of interest to the database.
3. The many-to-one relationship in a database means:
A. Many records in one table can correspond to one record in another table.
B. One record in a table corresponds to many records in another table.
C. A record in one table corresponds to a unique record in another table.
D. One record in a table corresponds to no records in another table.
Answer: A
Rationale: A many-to-one relationship means that many records in one table can
correspond to a single record in another table.
4. Which of the following is an example of a composite key?
A. A single column that uniquely identifies a record.
B. A combination of two or more columns that uniquely identify a record.
C. A key that contains duplicate values.
D. A key that relates to another table.
Answer: B
, Rationale: A composite key is made up of two or more columns in a table that
together uniquely identify a record.
5. In a many-to-many relationship, which of the following is typically required?
A. A composite primary key.
B. A foreign key.
C. A junction table.
D. A view.
Answer: C
Rationale: In many-to-many relationships, a junction table (also called an
associative table) is needed to handle the relationship between the two entities by
storing foreign keys from both entities.
6. The secondary key in a database is:
A. A key that is used to uniquely identify a record.
B. A key used for faster searches but does not have to be unique.
C. A key that references a primary key in another table.
D. A key that enforces referential integrity.
A. Schema-less design
B. Horizontal scalability
C. Strong consistency
D. Non-relational data model
Answer: C
Rationale: NoSQL databases are often designed for horizontal scalability and
flexibility with a schema-less structure. They may favor eventual consistency over
strict consistency.
2. In the context of entity-relationship (ER) modeling, an entity is represented by:
A. A rectangle.
B. An oval.
C. A diamond.
D. A hexagon.
Answer: A
,Rationale: In ER modeling, entities are represented by rectangles, which symbolize
the objects or things in the real world that are of interest to the database.
3. The many-to-one relationship in a database means:
A. Many records in one table can correspond to one record in another table.
B. One record in a table corresponds to many records in another table.
C. A record in one table corresponds to a unique record in another table.
D. One record in a table corresponds to no records in another table.
Answer: A
Rationale: A many-to-one relationship means that many records in one table can
correspond to a single record in another table.
4. Which of the following is an example of a composite key?
A. A single column that uniquely identifies a record.
B. A combination of two or more columns that uniquely identify a record.
C. A key that contains duplicate values.
D. A key that relates to another table.
Answer: B
, Rationale: A composite key is made up of two or more columns in a table that
together uniquely identify a record.
5. In a many-to-many relationship, which of the following is typically required?
A. A composite primary key.
B. A foreign key.
C. A junction table.
D. A view.
Answer: C
Rationale: In many-to-many relationships, a junction table (also called an
associative table) is needed to handle the relationship between the two entities by
storing foreign keys from both entities.
6. The secondary key in a database is:
A. A key that is used to uniquely identify a record.
B. A key used for faster searches but does not have to be unique.
C. A key that references a primary key in another table.
D. A key that enforces referential integrity.
