---
id: sql-like
title: "SQL Like"
category: "Database"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["SQL LIKE Operator", "LIKE operator", "SQL 패턴 매칭"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.9
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["sql", "database", "w3schools", "like", "pattern-matching", "where"]
raw_sources: ["https://www.w3schools.com/sql/sql_like.asp"]
applied_in: []
github_commit: ""
---

# [[SQL Like]]

## 🎯 한 줄 통찰 (One-line insight)
LIKE searches for a text pattern in a column using the `%` (any characters) and `_` (single character) wildcards, and can express starts-with/ends-with/contains matching. [S1]

## 🧠 핵심 개념 (Core concepts)
- **LIKE operator** — used in a WHERE clause to search for a specified pattern within a column's text data. [S1]
- **Syntax** — `SELECT ... FROM table_name WHERE columnN LIKE pattern;`. [S1]
- **`%` wildcard** — represents zero, one, or multiple characters. [S1]
- **`_` wildcard** — represents exactly one character. [S1]
- **No wildcard** — without a wildcard, LIKE requires an exact match. [S1]

## 🧩 추출된 패턴 (Extracted patterns)
- **Positional-% recipe** — `pattern%` = starts with, `%pattern` = ends with, `%pattern%` = contains, `pattern` (no `%`) = exact match. [S1]
- **Combine with AND/OR** — multiple LIKE conditions can be combined, e.g. `CustomerName LIKE 'a%' OR CustomerName LIKE 'b%'`. [S1]
- **Wildcard stacking** — `%` and `_` can be combined in one pattern, e.g. `'a__%'` (starts with "a", at least 3 chars) or `'_r%'` ("r" in second position). [S1]

## 📖 세부 내용 (Details)
- Starts with: `WHERE CustomerName LIKE 'a%';`. [S1]
- Contains: `WHERE city LIKE '%on%';`. [S1]
- Single-character wildcard: `WHERE city LIKE 'l_nd__';` (l + 1 wildcard char + "nd" + 2 wildcard chars). [S1]
- Ends with: `WHERE CustomerName LIKE '%a';`. [S1]
- Starts-and-ends: `WHERE CustomerName LIKE 'b%s';`. [S1]
- Exact match (no wildcard): `WHERE Country LIKE 'Spain';`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
소스에서 모순되는 정보는 발견되지 않음.

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 다음 챕터인 SQL Wildcards에서 `[]`, `-`, `^` 같은 추가 와일드카드 문법이 확장된다. [S1]

## 💻 코드 패턴 (Code patterns)
Starts-with / contains / ends-with (SQL):
```sql
SELECT * FROM Customers WHERE CustomerName LIKE 'a%';   -- starts with
SELECT * FROM Customers WHERE city LIKE '%on%';          -- contains
SELECT * FROM Customers WHERE CustomerName LIKE '%a';    -- ends with
```

## ✅ 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)
- **상위/루트:** [[SQL Tutorial]]
- **관련 개념:** [[SQL Where]], [[SQL Wildcards]], [[SQL Not]]
- **참조 맥락:** 텍스트 패턴 매칭이 필요한 모든 검색 쿼리의 기반 문법 — 다음 챕터 Wildcards에서 문법이 확장된다.

## 📚 출처 (Sources)
- [S1] W3Schools — SQL LIKE Operator — https://www.w3schools.com/sql/sql_like.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "SQL LIKE Operator" page (Astra wiki-curation, P-Reinforce v3.1 format).
