What are the possible values for a BOOLEAN field 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
MySQL doesn't have a native BOOLEAN type. It uses TINYINT(1) where 0 = false, 1 = true, and any non-zero value is treated as true in conditions.
CREATE TABLE users (is_active TINYINT(1) DEFAULT 1);
PostgreSQL, however, has a true BOOLEAN type accepting TRUE, FALSE, and NULL.
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