DMC Study Guide 2026
Everything you need to pass the DMC exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📚 DMC Topics to Study (22)
✍️ Sample DMC Questions & Answers
1. What is a slowly changing dimension (SCD) Type 1?
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.
2. In an ERD, what does the notation '1' on one side and 'M' on the other side of a relationship line indicate?
The 1:M notation indicates a one-to-many relationship where one instance of the first entity can relate to many instances of the second.
3. What is the primary purpose of a data quality scorecard in enterprise data modeling?
A data quality scorecard provides a structured view of quality metrics versus targets, enabling stakeholders to track and improve data health over time.
4. What does GDPR require of data models that store personal data of EU residents?
GDPR requires that data systems support the right to access, rectify, port, and erase personal data — data models must be designed to accommodate these rights technically.
5. What is the primary goal of a conceptual data model?
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.
6. Which ERD notation style uses rectangles for entities, diamonds for relationships, and ovals for attributes?
Chen notation, developed by Peter Chen in 1976, uses rectangles for entities, diamonds for relationships, and ovals for attributes in its ERD representation.