✅ SELECT 문법 (기본 구조)SELECT 컬럼1, 컬럼2FROM 테이블명WHERE 조건식ORDER BY 컬럼 ASC/DESCLIMIT 숫자; WHERE: 조건 필터링 (=, LIKE, BETWEEN, IN, IS NULL)WHERE column = '값'WHERE column LIKE '%값%' -- 부분 문자열 검색WHERE column BETWEEN A AND B -- 범위 검색WHERE column IN ('A', 'B')WHERE column IS NULL / IS NOT NULL ✅ 집계함수 (GROUP BY, HAVING)SELECT 부서, COUNT(*) AS 인원수FROM 직원GROUP BY 부서HAVING COUNT(*) >= 5;주요 집계함수: COUNT, SUM, ..