UNIT-5

What is the primary purpose of a query optimizer?

• To execute queries as written without modification

• To determine the most efficient way to execute a query

• To store data in a more optimized format

• To visualize query results in dashboards

Which of the following factors does a query optimizer consider?

• Index usage

• Execution cost estimation

• Join order optimization

• All of the above

What is the first step in the life cycle of a query?

• Execution

• Parsing

• Optimization

• Query transformation

Which of the following can help improve query performance?

• Adding indexes on frequently queried columns

• Using SELECT * in queries

• Running queries without WHERE conditions

• Avoiding the use of indexes

Which of the following is a key difference between querying batch data and streaming data?

• Batch queries run continuously, while streaming queries run once

• Streaming queries process data in real-time, while batch queries process data at scheduled intervals

• Streaming queries always require complex joins

• Batch queries are always faster than streaming queries

Which of the following is commonly used to model streaming data?

• Data Warehouse Schema

• Time-Series Data Model

• Normalized Relational Schema

• Document-based NoSQL Model

Which type of system is best suited for processing streaming data?

• Relational Databases (RDBMS)

• Stream Processing Frameworks (e.g., Apache Flink, Apache Kafka Streams)

• Data Warehouses

• Hadoop MapReduce

Which of the following best describes a transformation in data processing?

• Moving data between storage locations

• Applying changes to raw data to make it usable for analysis

• Storing raw data without modification

• Deleting redundant data

Which of the following is an example of a real-time data transformation?

• Aggregating customer transactions per minute

• Running a daily ETL pipeline

• Generating a static report once a month

• Compressing data for archival storage

Which technology is commonly used for streaming transformations?

• Apache Kafka Streams

• PostgreSQL

• Amazon S3

• Microsoft Excel