DMC Data Quality and Integrity 1 — Questions and Answers
Question 1: Which data quality dimension measures the degree to which data values fall within acceptable ranges and adhere to defined business rules?
- Completeness
- Validity (Correct answer)
- Consistency
- Timeliness
Correct answer: Validity
Validity measures whether data conforms to defined formats, ranges, and business rules, ensuring values are acceptable within the data model.
Question 2: A data model enforces referential integrity by ensuring that every foreign key value in a child table corresponds to an existing primary key in the parent table. What happens when this rule is violated?
- The record is automatically corrected
- An orphan record is created (Correct answer)
- The parent record is duplicated
- The foreign key is set to the maximum value
Correct answer: An orphan record is created
A referential integrity violation results in an orphan record — a child record that references a non-existent parent, breaking relationships in the data model.
Question 3: In the context of data quality, which term describes data that exists in multiple places but has conflicting values?
- Duplicate data
- Stale data
- Inconsistent data (Correct answer)
- Sparse data
Correct answer: Inconsistent data
Inconsistent data refers to the same data element having different values across systems or tables, which violates the consistency dimension of data quality.
Question 4: Which constraint type in a relational data model ensures that a column or set of columns cannot contain NULL values?
- Check constraint
- Unique constraint
- NOT NULL constraint (Correct answer)
- Default constraint
Correct answer: NOT NULL constraint
A NOT NULL constraint enforces the completeness dimension of data quality by requiring that a column always has a value.
Question 5: A data steward discovers that customer records have phone numbers stored as both '555-1234' and '5551234'. Which data quality dimension is primarily affected?
- Accuracy
- Consistency
- Conformity (Correct answer)
- Uniqueness
Correct answer: Conformity
Conformity measures whether data follows specified formats and standards; inconsistent phone number formats indicate a conformity failure.
Question 6: What is the primary purpose of a data quality scorecard in enterprise data modeling?
- To rank database administrators by performance
- To measure and communicate data quality metrics against defined thresholds (Correct answer)
- To document the physical storage layout
- To map ETL pipeline throughput
Correct answer: To measure and communicate data quality metrics against defined thresholds
A data quality scorecard provides a structured view of quality metrics versus targets, enabling stakeholders to track and improve data health over time.
Question 7: Which technique is commonly used in data modeling to detect and merge duplicate entity records that represent the same real-world object?
- Data partitioning
- Master data management (MDM) (Correct answer)
- Horizontal scaling
- Schema migration
Correct answer: Master data management (MDM)
Master Data Management (MDM) provides processes and tools to identify, merge, and maintain a single authoritative record for duplicate entities across systems.
DMC Data Quality and Integrity 1
Which data quality dimension measures the degree to which data values fall within acceptable ranges and adhere to defined business rules?