What is normalization and denormalization? When would you use each?
SQLmedium
2
What is a window function? Explain with an example.
SQLmedium
3
Write complex SQL queries involving multiple joins, subqueries, and data aggregation logic.
SQLmedium
4
Explain how Adaptive Query Execution changes the economics of Spark tuning. What problems does it solve at runtime, and when might you still need manual intervention (e.g., salting, broadcast hints)?
Spark/Big Datamedium
5
How do you handle data skewness in Spark?
Spark/Big Datamedium
6
What is Adaptive Query Execution (AQE) in Spark 3.x, and how does it improve performance?
Spark/Big Datamedium
7
When and how do you use Broadcast Join in Spark?
Spark/Big Datamedium
8
What is broadcasting in Spark, and why is it used? Can you give an example of its use?
Spark/Big Datamedium
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