Practice Test GeeksDMC - Data Modeling Certification Practice Test
← All DMC Flashcard Decks

Database Normalization and Design Patterns Flashcards

6 cards from real DMC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 Database Normalization and Design Patterns flashcards as text

  1. What is the Star Schema pattern used in data warehouse modeling?

    Answer: A central fact table surrounded by denormalized dimension tables, optimized for analytical query performance

    The Star Schema places a central fact table containing measures and foreign keys surrounded by denormalized dimension tables, enabling fast analytical queries with simple joins.

  2. How does a Snowflake Schema differ from a Star Schema?

    Answer: Snowflake normalizes dimension tables into sub-dimensions, reducing redundancy but requiring more joins; Star denormalizes for simplicity

    A Snowflake Schema normalizes dimension tables by splitting hierarchies into separate tables, reducing data redundancy at the cost of more complex queries requiring additional joins.

  3. What is a fact table in dimensional modeling?

    Answer: A central table in a star or snowflake schema that stores measurable business events with foreign keys to dimension tables

    A fact table stores measurable, quantitative data about business events — such as sales amounts, quantities, or counts — along with foreign keys linking to the relevant dimensions.

  4. What is a slowly changing dimension (SCD) Type 1?

    Answer: A method of handling attribute changes by simply overwriting the old value, preserving no history

    SCD Type 1 handles changes by overwriting the old attribute value with the new one, which is simple but destroys historical data — appropriate when history is not needed.

  5. In a Data Vault model, what does a Hub contain?

    Answer: The unique business keys of a core business entity along with metadata about its source and load date

    A Hub in Data Vault modeling stores the unique business keys for a core business concept, along with a surrogate key, load date, and record source — no descriptive attributes.

  6. In Data Vault modeling, what is the purpose of a Link?

    Answer: To capture the relationships and associations between two or more Hubs

    A Link in Data Vault modeling captures the many-to-many or associative relationships between Hubs, storing only the foreign keys to the related Hubs plus metadata.

How this page was made: written with AI tools and published by Nathan Beja, founder of Practice Test Geeks, who is responsible for its content. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy

Sources & references

Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy

  1. technicspub.com — Test delivery, eligibility, fees, exam format, passing score, retake policy, score release, time limit, exam information · verified Oct 2026