Canonical: this is a cross-post. The original lives at https://four-leaf.ai/blog/sql-interview-guide
Key takeaways
A SQL interview is a translation test. The syntax is the easy half, and most candidates who fail were fluent in SQL. What sinks them is starting to type before the question is pinned down, or writing a correct query that answers something nobody asked. The round scores three things: whether you clarify before you write, whether your query is correct on the edge cases, and whether you can explain your reasoning while your hands are moving. It also looks meaningfully different depending on whether you're interviewing as a data analyst, a data scientist, or an engineer.
What does a SQL interview test?
The round tests whether you can turn an underspecified business question into a query that survives contact with real data. Interviewers rarely hand you a clean specification, because the job never does either.
