Commerce
Shopify interview themes
What people report studying for — not a take-home dump. Last editorial update 2026-05-20.
Rounds you should expect
dbt + SQL
Refunds that arrive after the order incremental window. Lookback vs a payments fact.
From the question bank
hard · SQL · SQL
Deduplicate to the latest customer row. Why not filter the window in WHERE?
Practice →medium · SQL · SQL
You need “customers who ordered in January and never in February.” Write the shape, not the dialect.
Practice →easy · Warehouse · Snowflake
DIRECTORY tables and a stage full of JSON. Why is SELECT $1:id from the stage a bad gold pattern?
Practice →easy · Data modeling · dbt
What belongs in staging versus a mart?
Practice →medium · Data modeling · dbt
A model is ephemeral and 20 joins. Why is CI sad?
Practice →medium · Data modeling · dbt
You need yesterday’s incremental plus a 3-day lookback for late CDC. How do you not rebuild the month?
Practice →medium · Data modeling · dbt
state:modified+ in CI still rebuilt 80 models. First three checks?
Practice →easy · Orchestration · Airflow
catchup=False forever. What history did you silently skip?
Practice →hard · Warehouse · Databricks
Auto Loader vs a COPY into a table every hour. When is streaming the simpler design?
Practice →easy · Streaming · Kafka
Compaction vs deletion retention. When do you use a compacted topic?
Practice →medium · Streaming · Kafka
Tombstones — what do you produce for a CDC delete?
Practice →medium · Streaming · Kafka
A compacted topic still has two values for one key. Why?
Practice →