---
id: php-mysql-delete
title: "PHP MySQL Delete"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["DELETE FROM", "PHP MySQL 삭제"]
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: ["php", "programming", "w3schools", "mysql", "delete"]
raw_sources: ["https://www.w3schools.com/php/php_mysql_delete.asp"]
applied_in: []
github_commit: ""
---

# [[PHP MySQL Delete]]

## 🎯 한 줄 통찰 (One-line insight)
Omitting the `WHERE` clause in a `DELETE` statement deletes EVERY record in the table — the source flags this with an explicit "NOTE" warning, since `DELETE FROM MyGuests` (without `WHERE id=3`) would wipe the entire table rather than doing nothing or erroring. [S1]

## 🧠 핵심 개념 (Core concepts)
- **`DELETE FROM table WHERE condition`** — removes matching records. [S1]
- **WHERE is what limits the blast radius** — omitting it deletes ALL records in the table. [S1]
- **Executed like other write operations** — `$conn->query($sql)` (MySQLi OOP), `mysqli_query($conn, $sql)` (procedural), `$conn->exec($sql)` (PDO). [S1]

## 📖 세부 내용 (Details)
- Delete by ID: `$sql = "DELETE FROM MyGuests WHERE id=3"; if ($conn->query($sql) === TRUE) { echo "Record deleted successfully"; } else { echo "Error deleting record: " . $conn->error; }`. [S1]
- PDO equivalent: `$sql = "DELETE FROM MyGuests WHERE id=3"; $conn->exec($sql); echo "Record deleted successfully";` wrapped in try/catch(PDOException). [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **WHERE 절 생략의 파괴적 결과**: WHERE 절을 생략하면 테이블의 모든 레코드가 삭제된다는 점이 명시적 경고(NOTE)로 강조됨. [S1]

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — id=3 게스트 레코드만 삭제하는 것이 안전한 조건부 삭제의 표준 패턴이다. [S1]

## 💻 코드 패턴 (Code patterns)
Deleting a specific record, never omitting WHERE (SQL/PHP):
```php
$sql = "DELETE FROM MyGuests WHERE id=3"; // WHERE is mandatory to avoid deleting everything
if ($conn->query($sql) === TRUE) {
    echo "Record deleted successfully";
}
```

## ✅ 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:** [[PHP Tutorial]]
- **관련 개념:** [[PHP MySQL Select Order By]], [[PHP MySQL Update]]
- **참조 맥락:** 레코드 삭제 — 레코드 수정(Update) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — PHP MySQL Delete Data — https://www.w3schools.com/php/php_mysql_delete.asp

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