OR vs AND?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of SQL & Databases conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
AND requires ALL conditions to be true. OR requires ANY to be true. Use parentheses to control precedence — AND binds tighter than OR.
-- Without parentheses, this is parsed as:
-- WHERE (age > 18 AND city = 'NY') OR status = 'active'
SELECT * FROM customers
WHERE age > 18 AND (city = 'NY' OR city = 'LA');
Candidate Response Strategy & Interview Tips
- Start with a concise one-sentence summary: Deliver a direct, confident answer first before expanding into nuances.
- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
- Prepare for interviewer follow-ups: Technical hiring panels frequently probe deeper into concurrency, backward compatibility, or alternative libraries.