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Amazon interview themes
What people report studying for — not a take-home dump. Last editorial update 2026-06-28.
Rounds you should expect
SQL
Top-N per partition, window vs self-join, and a join that must not explode.
AWS data
Tiny files on S3, Athena bytes scanned, when Glue is enough vs EMR.
From the question bank
easy · SQL · SQL
Write top-3 orders per country. What breaks if you use RANK() instead of ROW_NUMBER()?
Practice →medium · SQL · SQL
A query is correct but scans last year. How do you prove partition pruning?
Practice →hard · SQL · SQL
EXPLAIN says Hash Join. When do you want Nested Loop instead?
Practice →easy · Streaming · Kafka
Kafka vs Kinesis — what is the real trade?
Practice →medium · Coding · Spark
repartition vs coalesce. When is each correct?
Practice →hard · Coding · Spark
S3 vs HDFS locality. Why was the same job faster on HDFS?
Practice →hard · Cloud · AWS
S3 + Glue + Athena vs Redshift — how do you choose in sixty seconds?
Practice →medium · Cloud · AWS
Glue job vs Lambda vs EMR. Who owns a 40-minute Spark transform?
Practice →medium · Cloud · AWS
Kinesis vs MSK vs SQS. One sentence each.
Practice →medium · Cloud · AWS
Redshift DISTKEY / SORTKEY (or AUTO). What mistake shows up as a broadcast of a 2 TB table?
Practice →easy · Cloud · AWS
S3 committers — why did a failed Spark write leave a partial prefix?
Practice →medium · Cloud · AWS
Cost tags on Glue/Athena/Redshift. Why do interviewers ask?
Practice →