Details of students whose FirstName starts with 'K'?
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
To find records where a text column begins with a specific letter or prefix, use the LIKE operator with the % wildcard:
SELECT *
FROM Students
WHERE FirstName LIKE 'K%';
### How Wildcards Work:
%: Matches zero, one, or multiple arbitrary characters ('K','Kevin','Katherine')._: Matches exactly one single character ('K_'matches'Ka', but not'Kevin').- *Index efficiency:* Prefix wildcards like
'K%'leverage B-tree indexes effectively. Leading wildcards like'%K'cannot use standard B-tree indexes and cause full table scans.
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.