What is a virtual table in MySQL?
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
In MySQL and relational databases, a virtual table is called a View:
CREATE VIEW active_customer_summary AS
SELECT id, first_name, last_name, email
FROM Customers
WHERE is_active = 1;
### Characteristics of a View:
- A view does not store physical data rows on disk (unlike base tables).
- It stores a pre-packaged
SELECTquery definition. - When an application queries the view (
SELECT * FROM active_customer_summary), the database dynamically runs the underlying query against the base tables.
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.