Practice Questions
Question 1
Which structure is used to store relational data?
A. Key-value pairs
B. Graph nodes and edges
C. Tables with rows and columns
D. JSON documents
✅ Answer: C
Explanation:
Relational data is organized in tables consisting of rows and columns.
Question 2
What is the purpose of a primary key in a relational table?
A. To link tables together
B. To uniquely identify each row
C. To store duplicate values
D. To define column data types
✅ Answer: B
Explanation:
A primary key uniquely identifies each record and cannot contain duplicates or null values.
Question 3
Which element is used to create relationships between tables?
A. Index
B. Column constraint
C. Foreign key
D. Schema
✅ Answer: C
Explanation:
A foreign key links one table to another by referencing a primary key.
Question 4
Which statement best describes a schema in a relational database?
A. A collection of unstructured files
B. A visual report of data
C. The structure defining tables, columns, and data types
D. A backup of the database
✅ Answer: C
Explanation:
A schema defines how data is structured, including tables, columns, and data types.
Question 5
Which language is used to query relational databases?
A. Python
B. JSON
C. SQL
D. HTML
✅ Answer: C
Explanation:
Structured Query Language (SQL) is used to query and manage relational data.
Question 6
Which constraint ensures that a column cannot contain null values?
A. UNIQUE
B. CHECK
C. NOT NULL
D. FOREIGN KEY
✅ Answer: C
Explanation:
The NOT NULL constraint ensures that a value must be provided for that column.
Question 7
Which concept reduces data redundancy by organizing data into multiple related tables?
A. Indexing
B. Normalization
C. Partitioning
D. Replication
✅ Answer: B
Explanation:
Normalization reduces redundancy and improves data integrity.
Question 8
Which type of relationship allows one record in a table to relate to many records in another table?
A. One-to-one
B. One-to-many
C. Many-to-one
D. Many-to-many
✅ Answer: B
Explanation:
One-to-many relationships are common in relational databases (e.g., one customer → many orders).
Question 9
Which property ensures that all parts of a transaction succeed or fail together?
A. Consistency
B. Isolation
C. Atomicity
D. Durability
✅ Answer: C
Explanation:
Atomicity ensures transactions are completed fully or not at all.
Question 10
Which Azure service is specifically designed for relational data?
A. Azure Blob Storage
B. Azure Cosmos DB
C. Azure SQL Database
D. Azure Data Lake Storage
✅ Answer: C
Explanation:
Azure SQL Database is a fully managed relational database service.
✅ Quick Exam Takeaways
For DP-900, remember:
✔ Relational data = tables (rows + columns)
✔ Schema defines structure
✔ Primary keys uniquely identify rows
✔ Foreign keys create relationships
✔ Use SQL for querying
✔ Constraints enforce data integrity
✔ Normalization reduces redundancy
✔ Supports ACID transactions
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