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Diagnostic Answers — DM5-049–060

DM5-049 — A

Why: canonical models represent shared/standardized data-in-motion message structures between systems.
Distractors: B = stored logical data at rest; C = materialized view; D = operational DB PDM.
Source: pp. 159–160. Confusion: canonical vs physical database model.

DM5-050 — B

Why: standard view is virtual/query-time; materialized view stores an instantiated result refreshed at predetermined times.
Distractors: A reverses storage; C ignores query logic; D is unrelated.
Source: pp. 159–160. Confusion: view vs materialized view.

DM5-051 — C

Why: vertical partitioning divides a structure by columns.
Distractors: horizontal divides rows; denormalization duplicates/combines; generalization is abstraction.
Source: pp. 160–161. Confusion: vertical vs horizontal partition.

DM5-052 — D

Why: partitioning records by year splits rows → horizontal partitioning.
Distractors: vertical = columns; specialization/canonical are unrelated.
Source: pp. 160–161. Confusion: vertical vs horizontal partition.

DM5-053 — A

Why: denormalization is intentional physical redundancy/structural change justified by requirements, with synchronization/error trade-offs.
Distractors: it is not automatically required after 3NF, does not eliminate redundancy, and is not conceptual-only.
Source: pp. 160–162. Confusion: normalization vs denormalization.

DM5-054 — B

Why: 1NF includes valid PK/atomic values/no repeating groups and source-aligned resolution of M:M via associative structures.
Distractors: A = 2NF; C = 3NF; D points to BCNF-level concerns.
Source: pp. 162–165. Confusion: 1NF vs 2NF vs 3NF.

DM5-055 — C

Why: 2NF removes partial dependency: every non-key attribute depends on the complete minimal key.
Distractors: A = 1NF; B = 3NF; D = higher form.
Source: pp. 163–165. Confusion: 2NF vs 1NF/3NF.

DM5-056 — D

Why: 3NF memory rule: key, whole key, nothing but key.
Distractors: A is nonsense; surrogate and ternary requirements are unrelated.
Source: pp. 163–165. Confusion: 3NF vs lower forms.

DM5-057 — A

Why: Chapter 5 notes that unqualified “normalized model” usually means 3NF.
Distractors: 1NF is too low; BCNF/5NF are more specialized and not the usual default.
Source: pp. 163–165. Confusion: 3NF vs higher forms.

DM5-058 — B

Why: generalization moves common properties/relationships upward into a supertype.
Distractors: A = specialization; C = denormalization; D = physical mapping.
Source: current answer key pp. 165–167. Confusion: generalization vs specialization.

DM5-059 — C

Why: specialization creates subtypes for distinguishing properties while inheriting supertype properties.
Distractors: A = generalization; B removes distinctions; D is key design.
Source: pp. 165–167. Confusion: specialization vs generalization.

DM5-060 — D

Why: core modeling deliverables include diagrams, definitions, issues/outstanding questions, and lineage.
Distractors: A is too physical; B is not the listed modeling set; C are technology assets.
Source: p. 124. Confusion: modeling deliverables vs implementation assets.

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