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id, title, category, status, verification_status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, created_at, updated_at, review_reason, merge_history, tags, raw_sources, applied_in, github_commit
id title category status verification_status canonical_id aliases duplicate_of source_trust_level confidence_score created_at updated_at review_reason merge_history tags raw_sources applied_in github_commit
sql-having SQL Having Database draft conceptual
SQL HAVING Clause
HAVING clause
SQL 그룹 조건절
B 0.9 2026-07-04 2026-07-04
sql
database
w3schools
having
groupby
aggregate
https://www.w3schools.com/sql/sql_having.asp

SQL Having

🎯 한 줄 통찰 (One-line insight)

HAVING filters GROUP BY results based on aggregate conditions, applying AFTER grouping — unlike WHERE, which filters individual rows BEFORE grouping. [S1]

🧠 핵심 개념 (Core concepts)

  • HAVING clause — filters the results of a GROUP BY query based on aggregate functions. [S1]
  • WHERE vs. HAVING — WHERE filters individual rows before grouping; HAVING filters groups after aggregation. [S1]
  • SyntaxSELECT column1, aggregate_function(column2), column3, ... FROM table_name WHERE condition GROUP BY column1, column3 HAVING condition ORDER BY column_name;. [S1]

🧩 추출된 패턴 (Extracted patterns)

  • WHERE + GROUP BY + HAVING composition — a query can filter rows first (WHERE), group them, then filter the resulting groups (HAVING) — e.g. restrict to two named employees, group by last name, then keep only groups with more than 25 orders. [S1]

📖 세부 내용 (Details)

  • Countries with more than 5 customers: SELECT Country, COUNT(CustomerID) AS [Number of Customers] FROM Customers GROUP BY Country HAVING COUNT(CustomerID) > 5;. [S1]
  • Same, sorted descending: ... GROUP BY Country HAVING COUNT(CustomerID) > 5 ORDER BY COUNT(CustomerID) DESC;. [S1]
  • Employees with more than 10 orders, via JOIN + GROUP BY + HAVING: SELECT Employees.LastName, COUNT(Orders.OrderID) AS NumberOfOrders FROM Orders INNER JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID GROUP BY LastName HAVING COUNT(Orders.OrderID) > 10;. [S1]
  • Combined WHERE + GROUP BY + HAVING: filter to two named employees first, then keep only those with more than 25 orders. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

소스에서 모순되는 정보는 발견되지 않음.

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — "N건 이상인 그룹만 보기" 같은 리포팅 쿼리에서 GROUP BY와 항상 짝을 이뤄 쓰인다. [S1]

💻 코드 패턴 (Code patterns)

Filter groups by aggregate condition (SQL):

SELECT Country, COUNT(CustomerID) AS [Number of Customers]
FROM Customers
GROUP BY Country
HAVING COUNT(CustomerID) > 5;

검증 상태 및 신뢰도

  • 상태: draft
  • 검증 단계: conceptual
  • 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
  • 신뢰 점수: 0.90
  • 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

📚 출처 (Sources)

📝 변경 이력 (Change history)

  • 2026-07-04: Initial draft synthesized from the W3Schools "SQL HAVING Clause" page (Astra wiki-curation, P-Reinforce v3.1 format).