Data Modeling Fundamentals Flashcards

What is a recursive (or self-referencing) relationship in data modeling?

Answer: A relationship where an entity is associated with instances of itself

A recursive relationship occurs when instances of a single entity type are related to other instances of the same entity type, such as an employee managing other employees.

What is a subtype in data modeling?

Answer: A specialized category of a supertype entity that inherits its attributes

A subtype is a specialized version of a supertype entity that inherits all supertype attributes and relationships while adding its own distinct ones.

What principle ensures that every fact in a data model is stored in exactly one place?

Answer: Single Source of Truth (SSOT)

The Single Source of Truth principle ensures each fact is stored once and only once, eliminating redundancy and reducing inconsistency risk.

In an ERD, what does a crow's foot notation symbol at the end of a relationship line represent?

Answer: Many (zero or more)

In crow's foot notation, the multi-pronged symbol (crow's foot) indicates the 'many' side of a one-to-many or many-to-many relationship.

Which of the following best describes an associative entity (also known as an intersection or bridge entity)?

Answer: An entity that links two or more entities in a many-to-many relationship and may contain its own attributes

An associative entity resolves a many-to-many relationship by becoming its own entity with a composite key and potentially additional attributes.

What is the primary goal of a conceptual data model?

Answer: To capture high-level business concepts and their relationships independent of technology

A conceptual data model captures major business entities and relationships at a high level, focusing on what the business needs to track rather than how data will be stored.