How to prepare for a data analyst interview in three months
Three months can change your level, not just refresh it. The risk is drift: a plan for “later” quietly becomes no plan. Keep a weekly rhythm — about five hours a week — and a visible count of what is done.
Month 1 — foundations
about 5 hours a week
- Paste the posting — or two or three you like — into Prepare for a job and read the topics their interviews will likely cover. That is your syllabus.
- SQL 30 start to finish, a few problems a day; the daily problem keeps the streak alive on busy days.
- A cheat sheet card a day: metrics, SQL patterns, A/B basics. By the end of the month you have seen most cards once.
- Last weekend: your first work week at Carrot, a practice grocery delivery company — about 2–3 hours.
Month 2 — depth
about 5 hours a week
- Hard SQL: cohort retention, sessions from event gaps, 30-day LTV. Then Pandas 20 and Python problems if the posting asks.
- Twice a week, a case without an interviewer: your plan first, then the strong candidate’s walkthrough. Keep a list of what you keep missing.
- One take-home case with a deadline you set, and the “find the bugs” problems in all three tracks.
- A second work week. Compare the two scores: the second should be higher, and you should know why.
Month 3 — interview mode
about 5 hours a week
- A mock interview every week on a different stage — SQL, product case, A/B, Python, behavioral. A free account includes one; the Pro pass adds more.
- Build a story bank: six stories with a number at the end — a project, a disagreement, a mistake, a decision on incomplete data, a deadline, a time you changed someone’s mind.
- Each new posting goes into Prepare for a job; the readiness report marks each requirement Ready, Almost or Gap and tells you what still needs evidence.
- Last week: warm-ups only, your stories out loud, questions for the interviewer, logistics. No new topics.
Life got in the way? Keep the SQL habit and one mock interview a week; cut depth before you cut rhythm.
Three months later you can say yes to
Still unchecked after three months? It is a rhythm problem, not a knowledge problem: shrink the weekly plan until it actually happens.
Paste your posting
Offer shows the topics its interviews will likely cover and builds a plan for that job. Free, no card.