Career
Practice assessments
Short, timed question sets drawn from the reviewed quiz bank. The timer runs on the server; results and explanations appear after you submit. Practice only: not proctored, not an employer test.
- Cleaning fundamentals
Profiling, missing values, text and Unicode, and quarantine decisions.
8 questions · 12 minutes
- Types, dates and money
Identifiers, booleans, ambiguous dates, offsets, locales and exact decimals.
8 questions · 12 minutes
- Joins and combining files
Null keys, fan-out, orphans, schema policies and lineage.
8 questions · 12 minutes
- Duplicates and entity resolution
Grain, survivor rules, evidence and review queues.
8 questions · 10 minutes
- SQL cleaning check
Casting, window functions, validation order and DuckDB behaviour.
8 questions · 10 minutes
- pandas cleaning check
Defaults that change data, nullable dtypes, merges and leakage.
8 questions · 10 minutes