Q121
Q121 In the context of data warehousing, what is "dimensional modeling"?
The process of converting unstructured text into a structured format
A technique for the physical design of databases
The creation of a conceptual model for analyzing data, typically involving facts and dimensions
The use of 3D models to represent data visually
Q122
Q122 Which data mining technique is used to uncover hidden patterns and relationships in data, but does not predict outcomes?
Classification
Regression
Clustering
Decision trees
Q123
Q123 How can you create an OLAP cube in SQL Server Analysis Services (SSAS)?
Using the CREATE CUBE statement in SQL
Through the SQL Server Management Studio (SSMS) interface
By executing a special OLAP cube creation script
Defining it in an XMLA script file
Q124
Q124 Which command is used to initiate the mining process on a dataset named "customer_data" using the Apriori algorithm in a data mining software tool?
MINING START customer_data USING Apriori
APRIORI MINING ON customer_data
USE Apriori ON customer_data
START MINING customer_data WITH Apriori
Q125
Q125 In a data warehousing environment, how is a materialized view refreshed to ensure it contains the latest data?
Refreshing it manually by executing a specific SQL command
Automatically, based on a schedule defined within the database management system
By triggering a script when the underlying data changes
All of the above
Q126
Q126 A materialized view in a data warehouse is not updating correctly.
What could be a reason?
The source data has not changed
The view is not scheduled for regular refreshes
The database lacks sufficient storage space
The view's definition does not include all necessary joins
Q127
Q127 During data mining, the model's accuracy drastically decreases when applied to new datasets.
What is a likely cause?
Overfitting to the training data
Underfitting to the training data
Insufficient data preprocessing
The data mining algorithm is not suitable for the task
Q128
Q128 How can "dimensional skew" in a data warehouse be identified and corrected?
By normalizing all tables to 3NF
By redistributing data to ensure uniform access patterns
By converting all OLAP cubes to ROLAP models
By implementing data compression techniques
Q129
Q129 What is the primary purpose of database encryption?
To increase database performance
To reduce data storage requirements
To protect sensitive data from unauthorized access
To improve data integrity
Q130
Q130 What does the principle of least privilege in database security entail?
Granting users minimal permissions necessary
Granting all users admin privileges
Storing all data centrally
Encrypting all data
Q131
Q131 Which database security feature limits data exposure by hiding certain data elements from unauthorized users?
Data masking
Data encryption
Data replication
Data indexing
Q132
Q132 What is SQL injection?
A method for encrypting SQL queries
A technique for improving SQL query performance
An attack by inserting malicious SQL into a query
A query optimization tool
Q133
Q133 What mechanism manages and validates user access in a database?
Data encryption algorithms
Data indexing strategies
Authentication and authorization
Data normalization techniques
Q134
Q134 How does role-based access control (RBAC) enhance database security?
By encrypting all data
By allowing unrestricted access
By assigning permissions to roles, not individuals
By using complex passwords
Q135
Q135 How can you grant a user read-only access to a specific table in SQL?
GRANT SELECT ON table_name TO user_name
ALTER TABLE table_name ALLOW READ FOR user_name
ENABLE READ ON table_name TO user_name
SET READ PERMISSION ON table_name FOR user_name
Q136
Q136 How do you create a new user with specific privileges in MySQL?
CREATE USER 'user_name' IDENTIFIED BY 'password'; GRANT privileges ON database_name.* TO 'user_name'
CREATE USER 'user_name' WITH privileges
USE 'user_name' WITH privileges
INITIATE USER 'user_name' WITH privileges
Q137
Q137 How do you revoke all privileges from a user in SQL?
REVOKE ALL PRIVILEGES FROM user_name
REVOKE ACCESS FROM user_name
REMOVE ALL PRIVILEGES user_name
DENY ALL FROM user_name
Q138
Q138 A user reports losing access to a table.
What could be the cause?
Permissions were revoked
The table was deleted
Database restored to a previous state
Permissions error
Q139
Q139 How can "privilege escalation" vulnerabilities be addressed?
Regular database software updates
Strict password policies
Regular security audits
Security patch implementation
Q140
Q140 How can SQL injection vulnerabilities be prevented?
Validating user inputs
Sanitizing user inputs
Using prepared statements
Sanitizing and using prepared statements
Q141
Q141 Which technology is commonly associated with real-time analytics and data processing?
Hadoop Distributed File System (HDFS)
Online Analytical Processing (OLAP)
Stream Processing
Data Warehousing
Q142
Q142 In the context of database technologies, what is a "Data Lake"?
A type of SQL database optimized for large-scale transactions
A storage repository that holds a vast amount of raw data
A new algorithm for data encryption
An advanced form of data masking technique
Q143
Q143 What differentiates Graph databases from traditional relational databases?
Graph databases use SQL for querying, while relational databases do not
Graph databases are primarily used for data warehousing
Graph databases are optimized for storing and querying data relationships
Relational databases cannot store complex, interconnected data
Q144
Q144 How do distributed ledger technologies (such as blockchain) enhance data security in database applications?
By centralizing data storage
By making data immutable and enabling transparent access
By encrypting all stored data
By limiting data access to administrators
Q145
Q145 What is the significance of "Edge Computing" in the context of database technologies?
Reducing cloud computing costs
Increasing the physical security of data centers
Minimizing latency by processing data closer to the source of data generation
Maximizing the efficiency of centralized databases
Q146
Q146 What SQL extension is used to query JSON data within a PostgreSQL database?
JSON_QUERY
SELECT JSON
JSONB_PATH_QUERY
GET_JSON_ITEM
Q147
Q147 How can you enable automatic scaling in a cloud-based NoSQL database service?
SET AUTOSCALE ON
MODIFY DATABASE SET SCALING=AUTOMATIC
UPDATE SCALING POLICY AUTO
Configure auto-scaling settings through the database's management console
Q148
Q148 A NoSQL database's response times degrade as data volume grows.
What strategy can improve performance?
Normalizing the database schema
Implementing sharding or partitioning strategies
Converting the NoSQL database to a SQL database
Decreasing the write consistency level
Q149
Q149 How can "query sprawl" in big data applications be managed effectively?
By limiting the number of users accessing the database
By using stricter schema definitions
By optimizing query execution and caching frequently accessed data
By reducing the size of the dataset
Q150
Q150 What is a common challenge when integrating IoT devices with real-time databases, and how can it be addressed?
Data volume exceeds storage capacity; addressed by increasing storage space
Data arrives faster than it can be processed; addressed by implementing stream processing solutions
IoT devices use incompatible data formats; addressed by standardizing data formats
All devices require constant internet connection; addressed by creating offline data processing capabilities
