Data Processing Data Validation and Quality 2 — Questions and Answers
Question 1: What is data deduplication?
- Removing duplicate records from a dataset (Correct answer)
- Adding backup copies of data
- Encrypting data for security
- Sorting data alphabetically
Correct answer: Removing duplicate records from a dataset
Data deduplication is the process of identifying and removing duplicate records to ensure each entry appears only once in a dataset.
Question 2: Which data quality dimension measures how up-to-date data is?
- Timeliness (Correct answer)
- Accuracy
- Completeness
- Consistency
Correct answer: Timeliness
Timeliness measures whether data is available and up-to-date when needed for processing or decision-making.
Question 3: What is referential integrity in relational databases?
- Foreign keys must correspond to existing primary keys in the referenced table (Correct answer)
- All tables must have the same number of rows
- Primary keys must be numeric
- Tables must be sorted by the primary key
Correct answer: Foreign keys must correspond to existing primary keys in the referenced table
Referential integrity ensures that a foreign key value in one table always refers to an existing primary key in the related table.
Question 4: Which method is commonly used to standardize data from multiple sources into a uniform format?
- Data normalization (Correct answer)
- Data encryption
- Data compression
- Data archiving
Correct answer: Data normalization
Data normalization reorganizes data into a consistent, standardized format to reduce redundancy and improve data quality across sources.
Question 5: What does 'data completeness' measure?
- The proportion of required data that is present and not missing (Correct answer)
- How fast data is processed
- How many tables are in a database
- The size of data files in gigabytes
Correct answer: The proportion of required data that is present and not missing
Data completeness measures whether all required data fields and records are present within the dataset.
Question 6: Which validation rule ensures a field contains only alphabetic characters?
- Data type check (Correct answer)
- Range check
- Presence check
- Uniqueness check
Correct answer: Data type check
A data type check verifies that the value in a field conforms to its expected data type, such as accepting only letters in a name field.
Data Processing Data Validation and Quality 2
What is data deduplication?