Interview prep
Pass the SQL screen.
Most analyst offers are decided in one round: the live SQL screen. An unseen schema, a ticking clock, and a question you have to solve while talking. Reading model answers doesn't train that — reps do. Here you rehearse the real thing: timed screens on schemas you've never seen, graded on the result by the same engine as the rest of the platform.
The SQL Screen
Medior screen
Streamora · subscription video
The screen that decides mid-level offers: latest-per-entity, top-N per group, the NOT IN NULL trap, month-over-month.
Senior screen
PulseBoard · product analytics
Funnel conversion, a fan-out that silently doubles revenue, and a running total — senior-screen classics.
What screens actually test
The same six question shapes come up in almost every loop — and each one hides a trap. Know the shape, name the trap out loud, and you read as experienced.
Aggregation + HAVING
Filtering groups with WHERE errors out — knowing why is the actual question.
HAVING and the Order SQL Runs InLatest per entity
Aggregating over the full history counts every stale row as current.
Cleaning the Noise ProWindow deltas
Month-over-month without LAG means fragile self-joins that misalign periods.
Window Functions ProFan-out joins
A duplicate key on the joined side silently doubles your total.
Aggregations That Lie ProTalk tracks — the verbal half
What to actually say for the questions SQL can’t grade: behavioral, modeling, stakeholder rounds. Structure stories as Situation → Task → Action → Result. Tap a question to see what a strong answer covers.