DMC Data Modeling Fundamentals 2

Question 1

What is a surrogate key?

Accepted Answer

A system-generated identifier with no business meaning

Answer

A surrogate key is a system-generated, meaningless identifier — typically an integer sequence — used solely to uniquely identify a row.

Question 2

Which of the following is a characteristic of a natural key?

Accepted Answer

It derives its value from business attributes that already exist

Answer

A natural key is derived from existing business data — such as a Social Security number or product barcode — that already has meaning in the real world.

Question 3

What is the key difference between a strong entity and a weak entity?

Accepted Answer

A weak entity cannot be uniquely identified without referencing its parent entity

Answer

A weak entity depends on a parent (owner) entity for its identification and cannot be uniquely identified by its own attributes alone.

Question 4

What does the term 'optionality' refer to in a data model?

Accepted Answer

Whether a relationship participation is mandatory or optional

Answer

Optionality describes whether an entity's participation in a relationship is mandatory (must exist) or optional (may or may not exist).

Question 5

Which modeling artifact is used to document the meaning and origin of a single data element across an enterprise?

Accepted Answer

Data element definition record

Answer

A data element definition record captures the business name, definition, data type, source, and steward of a single atomic piece of data.

DMC - Data Modeling Certification Practice Test

DMC - Data Modeling Certification Practice Test

DMC Data Modeling Fundamentals 2