Top 50 null values Interview Questions
The most frequently asked null values questions across all roles and companies, ranked by real interview frequency. Updated daily.
Calculate each customer's 30-day rolling engagement average using a PostgreSQL window function.
Use a scalar subquery and MAX to find the second distinct annual salary.
PCS Global Tech
Amazon Web ServicesReturn employees tied at the second and fourth highest non-null salary levels using salary ranking.
NCR Atleos
HashedIn by DeloitteExtract each Zynga player's demographic attributes from the users table and return them in player ID order.
ZyngaCalculate average energy consumption for each known TotalEnergies region.
TotalEnergiesUse joins and aggregation to return the 10 anime series with the highest total watch count.
CrunchyrollFind the second highest distinct salary from an employee table, handling duplicate and NULL salary values.
Amazon Web ServicesReturn the third largest distinct non-null number using PostgreSQL sorting and a subquery.
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