Diagnostic Answers — DM5-025–036
DM5-025 — A
Why: once one candidate becomes primary, other candidate keys are alternates.
Distractors: B is FK; C contradicts uniqueness; D is not the definition.
Source: pp. 136–137. Confusion: primary vs alternate.
DM5-026 — B
Why: a business key has business meaning and is used to recognize/retrieve an occurrence.
Distractors: A = surrogate; C = relationship migration; D is non-unique descriptive data.
Source: pp. 136–137. Confusion: business vs surrogate.
DM5-027 — C
Why: the current source treats business and surrogate classifications as mutually exclusive based on business meaning vs generated/no meaning.
Distractors: A/B contradict the distinction; D makes attribute count the deciding rule when it is not.
Source: pp. 136–137. Confusion: business vs surrogate.
DM5-028 — D
Why: Open/Closed/Cancelled is an enumerated list domain.
Distractors: range = boundaries; format = pattern; datatype alone cannot restrict to those values.
Source: pp. 139–140. Confusion: list vs range vs format.
DM5-029 — A
Why: 1–5 is a bounded range.
Distractors: list could enumerate but range is the direct clue; format is pattern; rule-based is more complex conditional logic.
Source: pp. 139–140. Confusion: range vs list vs rule.
DM5-030 — B
Why: AAA-9999 constrains the representation pattern, so Data Format.
Distractors: range/list/type do not enforce that shape.
Source: pp. 139–140. Confusion: format vs type.
DM5-031 — C
Why: conditional validity involving other information is rule-based.
Distractors: type/list/range cannot capture the stated conditional business logic.
Source: pp. 139–140. Confusion: rule-based vs simpler domain forms.
DM5-032 — D
Why: relational modeling emphasizes precise business meaning and normalized operational design/one fact in one place.
Distractors: dimensional = analytics; OO = class behavior; graph = connected traversal.
Source: current answer key pp. 140–144. Confusion: relational vs dimensional.
DM5-033 — A
Why: dimensional modeling is built around facts + dimensions for analytic querying.
Distractors: relational = operational integrity; Fact-Based = facts/roles verbalization; Time-Based = historization.
Source: pp. 144–148. Confusion: relational vs dimensional.
DM5-034 — B
Why: facts are measurements; dimensions give descriptive context.
Distractors: A reverses roles; C says they are synonyms; D misunderstands dimensional modeling.
Source: pp. 144–148. Confusion: fact vs dimension.
DM5-035 — C
Why: grain defines the semantic meaning/level of detail of one fact row.
Distractors: not dimension count, file size, or source normalization.
Source: pp. 145–147. Confusion: grain vs fact measure.
DM5-036 — D
Why: Type 1 overwrites and retains no history.
Distractors: Type 2 = new row; Type 3 = new column; conformance is shared definition, not history handling.
Source: pp. 147–148. Confusion: SCD Type 1 vs 2 vs 3.