Number of rows in inner / left / right / full outer join (join cardinality)
Out loud, in order: clarify, build it, check it, explain it.
Practise SQLData engineering interview · Finance, Payments & Fintech
SQL join-cardinality, pandas ETL, PySpark monitoring + unit tests, and a big-data ecosystem (Sqoop/Hive/HDFS) breadth check.
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And what its data engineers work with.
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Stages in the order candidates meet them.
5 stages. 4 rounds have reported questions, described below.
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The topics it covers and the questions candidates reported.
2 reported questions. See them below
2 reported questions. See them below
2 reported questions. See them below
2 reported questions. See them below
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By round. Questions marked Expected are written from the company's standards.
SQLHigh confidence
PythonHigh confidence
PySpark / SparkHigh confidence
Big-data ecosystemMedium confidence
Nobody reported these exact questions at Morgan Stanley. They are the questions a loop for each of its top topics is known to ask, so prepare for them as likely, not as confirmed.
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Ranked by how much of the evidence points at each topic.
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Do the first group before the second.
SQL (join cardinality, window functions)
Do first (3)Python pandas ETL
PySpark (monitoring/perf, unit tests); big-data ecosystem (Sqoop/Hive/HDFS/MapReduce)
Data modeling
ThenAWS scenarios
Behavioral
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Why candidates were turned down, as reported.
Cannot reason about join cardinality
SQL is named in 37 of 50 company accounts.No testing/CI-CD awareness
Shaky PySpark/ecosystem
Spark is named in 25 of 50 company accounts.Weak ETL design
Design is named in 27 of 50 company accounts.08
5 reported. Each opens and closes. Composites are labelled.
A recruiter call, a technical round (algorithms, data structures, SQL, testing and deployment), then a final loop. Questions included row counts for inner, left, right and full joins, writing a small ETL in pandas to a CSV, Spark monitoring and tuning, unit tests for SQL and PySpark, Hadoop tools, AWS scenarios and arrays and stacks.
What to take from it Know how to test your pipelines, not just write them.
Five rounds. The first was an online HackerRank test in four timed parts: SQL coding, multiple choice on Python, SQL and Unix, a data structures problem and database administration scenarios. The author says window functions, joins and database ideas matter most.
What to take from it Prepare for a mixed online test, with a clock.
The first round was an online test with two SQL questions and one Python question. The SQL tasks were removing duplicate rows and finding students absent three days in a row. This was in Mumbai in March 2026.
What to take from it Practise duplicates and consecutive-days problems.
A recruiter call about basic coding, then a spoken coding test in Python, SQL and Scala. Another candidate had a phone call with whiteboard coding and questions on unit and integration tests, deploying to production and finding errors.
What to take from it Be ready to talk about testing and deployment.
A 30-minute interview that ended after 15 minutes. The candidate had a bad experience.
What to take from it Some interviews are short and unclear. Stay calm and ask for feedback.
Good first-hand signal; testing/CI-CD awareness and join-cardinality reasoning stand out.
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Their reported questions, one at a time, against a stopwatch.
Number of rows in inner / left / right / full outer join (join cardinality)
Out loud, in order: clarify, build it, check it, explain it.
Practise SQL10
Pick your level and the weeks you have.
Built from what Morgan Stanley asks, strongest first. For the wider basics at your level, follow the Mid level plan alongside it.
Spark and big data
Read: Spark chaptersDrill: Spark playgroundSay it aloud: Spark questionsFull plan: Ace the Spark round
Python and coding
Read: Python chaptersDrill: Python practiceSay it aloud: Python questionsFull plan: Ace the Python round
Cloud and tools
Behavioral and communication
Read: Behavioral storytellingSay it aloud: Behavioral questions
Rehearse the Morgan Stanley loop
Run the question deckThen repeat your weakest topic once more.