SQL join-cardinality, pandas ETL, PySpark monitoring + unit tests, and a big-data ecosystem (Sqoop/Hive/HDFS) breadth check.
Cloud / platform
AWS scenarios; Spark/Hadoop (Sqoop, Hive, HDFS, MapReduce)
Reported difficulty
Not reported
Recruiter → technical (algo/DS/SQL + testing/deployment) → final loop. Real Qs: join row-count for inner/left/right/full; pandas pseudo-ETL to CSV; Spark monitoring/perf; unit tests with SQL & PySpark; Sqoop/Hive/HDFS/MapReduce; AWS scenarios; arrays & stacks.
Answered questions on what Morgan Stanley actually asks — each with the short answer, the answer that gets you rejected, and the follow-up.
Then build one and have it reviewed: design a daily orders pipeline or model a marketplace. No account.