Database Concepts & Terminology Flashcards

Which term describes the complete set of data values that an attribute can legally hold?

Answer: Domain

A domain defines the set of permissible values for an attribute, such as integers between 1 and 100 or valid date values.

In relational database terminology, a row in a table is also called a:

Answer: Tuple

A tuple is the formal relational term for a single row or record within a relation (table).

What is a 'schema' in the context of a relational database?

Answer: The structural definition of the database including tables and relationships

A schema is the logical structure or blueprint of the database, defining tables, columns, data types, and constraints without reference to actual data values.

Which concept ensures that every row in a table can be uniquely identified?

Answer: Primary key

A primary key is a column or combination of columns whose values uniquely identify each row in a table and cannot be NULL.

A foreign key in a relational database is used to:

Answer: Establish a link between data in two tables

A foreign key creates a referential link between a column in one table and the primary key of another table, enforcing referential integrity.

What does 'data redundancy' mean in database design?

Answer: The same data being stored in multiple places unnecessarily

Data redundancy refers to the unnecessary duplication of data across the database, which wastes storage and can lead to inconsistency during updates.

Which of the following best defines an 'entity' in database design?

Answer: A real-world object or concept about which data is stored

An entity is a distinguishable real-world object or concept—such as a person, place, or event—that has data stored about it in the database.