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Spark SQL
Data Engineer
Spark SQL questions
23 questions on Spark SQL for data engineers, easiest first.
Easy
7
Why DataFrames beat RDDs of objects
easy
What explode() does
easy
Orders lost after explode
easy
Scope of a temp view
easy
DROP TABLE on a managed table
easy
Fast count of unique visitors
easy
Grouping sales by month
easy
Medium
8
A UDF in the WHERE clause
medium
Latest row per customer
medium
Order of values from collect_list
medium
Making pivot faster
medium
Subtotals with rollup
medium
Same timestamp, different hour
medium
Parsing a JSON string column
medium
Changing each element of an array
medium
Hard
8
A window with no partitionBy
hard
Invalid casts after moving to Spark 4
hard
Pruning a fact table through a join
hard
Bad join order on Hive tables
hard
Using monotonically_increasing_id as a key
hard
first() gives different answers
hard
Where nulls go in a sort
hard
Rows produced by cube on two columns
hard
