Database Concepts Quiz

Which of the following is not a view of data?

• Internal

• Conceptual

• External

• Logical-Physical

Which model organizes data in a tree-like structure?

• Relational

• Hierarchical

• Network

• Object-oriented

Which of the following is a feature of the relational model?

• Data is stored in files

• Data is stored in tables

• Data is stored in hierarchies

• Data is stored as graphs

Which key uniquely identifies a tuple in a relation?

• Foreign key

• Composite key

• Primary key

• Candidate key

Relational Algebra is a ___.

• Procedural query language

• Non-procedural language

• Procedural query language

• Scripting language

Which SQL command is used to retrieve data?

• SELECT

• INSERT

• UPDATE

• DELETE

In an E-R diagram, an entity is represented by:

• Circle

• Rectangle

• Diamond

• Ellipse

Which is used to represent attributes in ER diagrams?

• Rectangle

• Ellipse

• Diamond

• Line

Which of the following is a type of attribute?

• Single-valued

• Multi-valued

• Derived

• All of the above

Mapping cardinality refers to:

• Number of attributes

• Number of entity instances related to another

• Number of databases

• None of the above