SQL Interviews Test Business Thinking, Not Just Syntax, Experts Say

A guide published by Four-Leaf AI argues that SQL interview rounds primarily evaluate a candidate's ability to translate vague business questions into precise queries, rather than test raw syntax knowledge. Interviewers deliberately leave prompts underspecified to see whether candidates clarify requirements before writing any code, a habit they consider more valuable than the query itself. The article identifies three question types that dominate most SQL rounds: join-and-aggregation, window functions, and open-ended business analysis against an unfamiliar schema. Strong candidates are distinguished by how they handle edge cases such as nulls, duplicate rows, and ambiguous definitions like 'active user.' The emphasis on SQL preparation is underscored by the Stack Overflow 2025 Developer Survey, which found 58.6% of developers used SQL in the past year, ranking it the third most-used language globally.