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Performance
Data Engineer
Performance questions
12 questions on Performance for data engineers, easiest first.
Easy
1
Partitioning a big table
easy
Medium
3
What causes a shuffle
medium
When to cache in Spark
medium
How Parquet skips data
medium
Hard
8
One task takes forever
hard
Millions of tiny files
hard
Cutting warehouse scan cost
hard
A slow Python UDF in PySpark
hard
Distinct users on billions of rows
hard
Clustering for two filter columns
hard
Choosing a Redshift DISTKEY
hard
Sensors blocking every worker
hard
