437 lines
20 KiB
Markdown
437 lines
20 KiB
Markdown
# 学生管理系统 — 数据库设计文档
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## 1. 数据库概述
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| 属性 | 说明 |
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|------|------|
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| 数据库名 | `sms`（学生管理系统 Student Manage System） |
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| 存储引擎 | InnoDB |
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| 字符集 | utf8mb4 |
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| 默认排序规则 | utf8mb4_unicode_ci |
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| 通用字段方案 | `id`、`create_time`、`update_time`、`is_deleted`、`delete_time` |
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---
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## 2. ER 关系图
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```
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┌──────────────────┐ ┌──────────────────┐ ┌──────────────────┐
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│ teachers │ │ classes │ │ students │
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├──────────────────┤ ├──────────────────┤ ├──────────────────┤
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│ id (PK) │ │ id (PK) │ │ id (PK) │
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│ num (UK) │ │ num (UK) │ │ num (UK) │
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│ name │ 1:N │ name │ 1:N │ name │
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│ age │ ----> │ class_start_time │ ----> │ age │
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│ sex │ │ │ │ sex │
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│ home_place │ │ head_teacher_id │ │ home_place │
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│ college │ │ coach_teacher_id │ │ college │
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│ specialty │ │ tutor_teacher_id │ │ specialty │
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│ enrollment_time │ └──────┬───────────┘ │ enrollment_time │
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│ graduate_time │ │ graduate_time │
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│ education │ │ education │
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│ work_experience │ │ │
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│ coach_area │ │ create_time │
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│ │ │ update_time │
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│ create_time │ ------------------│ is_deleted │
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│ update_time │ │ │ delete_time │
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│ is_deleted │ │ 1:N └──────────────────┘
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│ delete_time │ ▼ | 1:1
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└──────────────────┘ ┌──────────────────┐ ┌──────────────────┐
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│ scores │ │ employment │
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├──────────────────┤ ├──────────────────┤
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│ id (PK) │ │ id (PK) │
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│ sid (FK→students)│ │ sid (FK→students)│
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│ num │ │ class_id (FK) │
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│ score │ │ employment_open │
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│ │ │ _time │
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│ create_time │ │ offer_recived │
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│ update_time │ │ _time │
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│ is_deleted │ │ employment_comp │
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│ delete_time │ │ any │
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└──────────────────┘ │ employment_salar │
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│ y │
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│ │
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│ create_time │
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│ update_time │
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│ is_deleted │
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│ delete_time │
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└──────────────────┘
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```
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---
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## 3. 表结构详述
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### 3.1 teachers — 教师表
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| 字段名 | 类型 | 约束 | 说明 |
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|--------|------|------|------|
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| id | INT | PK, AUTO_INCREMENT | 主键 |
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| num | VARCHAR(30) | UNIQUE, NOT NULL, INDEX | 教师编号 |
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| name | VARCHAR(30) | NOT NULL | 姓名 |
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| age | INT | DEFAULT 18 | 年龄 |
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| sex | INT | DEFAULT 0 | 性别：0未知 1男 2女 |
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| home_place | VARCHAR(50) | NULL | 家乡 |
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| college | VARCHAR(50) | NULL | 毕业院校 |
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| specialty | VARCHAR(50) | NULL | 专业 |
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| enrollment_time | DATETIME | NULL | 入学时间 |
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| graduate_time | DATETIME | NULL | 毕业时间 |
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| education | VARCHAR(50) | NULL | 学历 |
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| work_experience | TEXT | NULL | 工作经验 |
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| coach_area | VARCHAR(50) | NULL | 教学方向：应用/项目/算法 |
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| create_time | DATETIME | NOT NULL | 创建时间 |
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| update_time | DATETIME | NOT NULL | 更新时间 |
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| is_deleted | BOOLEAN | DEFAULT FALSE | 软删除标志 |
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| delete_time | DATETIME | NULL | 删除时间 |
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**索引：**
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```sql
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PRIMARY KEY (id),
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UNIQUE KEY uk_tnum (num),
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KEY idx_num (num)
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```
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**外键：** 无（teachers 作为被引用方）
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---
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### 3.2 classes — 班级表
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| 字段名 | 类型 | 约束 | 说明 |
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|--------|------|------|------|
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| id | INT | PK, AUTO_INCREMENT | 主键 |
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| num | VARCHAR(30) | UNIQUE, NOT NULL, INDEX | 班级编号 |
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| name | VARCHAR(30) | NOT NULL | 班级名称 |
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| class_start_time | DATETIME | NULL | 开课时间 |
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| head_teacher_id | INT | NULL, FK→teachers.id | 班主任 ID |
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| coach_teacher_id | INT | NULL, FK→teachers.id | 授课老师 ID |
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| tutor_teacher_id | INT | NULL, FK→teachers.id | 助教老师 ID |
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| create_time | DATETIME | NOT NULL | 创建时间 |
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| update_time | DATETIME | NOT NULL | 更新时间 |
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| is_deleted | BOOLEAN | DEFAULT FALSE | 软删除标志 |
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| delete_time | DATETIME | NULL | 删除时间 |
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**索引：**
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```sql
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PRIMARY KEY (id),
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UNIQUE KEY uk_class_num (num),
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KEY idx_head_teacher (head_teacher_id),
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KEY idx_coach_teacher (coach_teacher_id),
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KEY idx_tutor_teacher (tutor_teacher_id)
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```
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**外键：**
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```sql
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CONSTRAINT fk_classes_head_teacher FOREIGN KEY (head_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE,
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CONSTRAINT fk_classes_coach_teacher FOREIGN KEY (coach_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE,
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CONSTRAINT fk_classes_tutor_teacher FOREIGN KEY (tutor_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE
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```
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---
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### 3.3 students — 学生表
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| 字段名 | 类型 | 约束 | 说明 |
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|--------|------|------|------|
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| id | INT | PK, AUTO_INCREMENT | 主键 |
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| num | VARCHAR(30) | UNIQUE, NOT NULL, INDEX | 学生编号 |
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| name | VARCHAR(30) | NOT NULL | 姓名 |
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| age | INT | DEFAULT 18 | 年龄 |
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| sex | INT | DEFAULT 0 | 性别：0未知 1男 2女 |
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| home_place | VARCHAR(50) | NULL | 家乡 |
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| college | VARCHAR(50) | NULL | 毕业院校 |
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| specialty | VARCHAR(50) | NULL | 专业 |
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| enrollment_time | DATETIME | NULL | 入学时间 |
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| graduate_time | DATETIME | NULL | 毕业时间 |
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| education | VARCHAR(50) | NULL | 学历 |
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| class_id | INT | NOT NULL, DEFAULT 0, INDEX | 所属班级 ID |
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| advisor_id | INT | NULL, FK→teachers.id | 顾问老师 ID |
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| create_time | DATETIME | NOT NULL | 创建时间 |
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| update_time | DATETIME | NOT NULL | 更新时间 |
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| is_deleted | BOOLEAN | DEFAULT FALSE | 软删除标志 |
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| delete_time | DATETIME | NULL | 删除时间 |
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**索引：**
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```sql
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PRIMARY KEY (id),
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UNIQUE KEY uk_snum (num),
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KEY idx_class_id (class_id),
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KEY idx_advisor_id (advisor_id),
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KEY idx_class_deleted (class_id, is_deleted) -- 复合索引，优化班级学生列表查询
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```
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**外键：**
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```sql
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CONSTRAINT fk_students_class FOREIGN KEY (class_id) REFERENCES classes(id) ON DELETE RESTRICT ON UPDATE CASCADE,
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CONSTRAINT fk_students_advisor FOREIGN KEY (advisor_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE
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```
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> **注意**：`class_id` 使用 `ON DELETE RESTRICT`，防止误删有学生的班级。
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---
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### 3.4 scores — 成绩表
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| 字段名 | 类型 | 约束 | 说明 |
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|--------|------|------|------|
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| id | INT | PK, AUTO_INCREMENT | 主键 |
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| sid | INT | NOT NULL, FK→students.id, INDEX | 学生 ID |
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| num | VARCHAR(30) | NOT NULL | 考核序次（如"第一次考核"） |
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| score | DECIMAL(10,2) | NOT NULL | 分数 |
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| create_time | DATETIME | NOT NULL | 创建时间 |
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| update_time | DATETIME | NOT NULL | 更新时间 |
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| is_deleted | BOOLEAN | DEFAULT FALSE | 软删除标志 |
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| delete_time | DATETIME | NULL | 删除时间 |
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**索引：**
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```sql
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PRIMARY KEY (id),
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UNIQUE KEY uk_sid_score (sid, num), -- 防止同一学生同一考核重复录入
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KEY idx_sid (sid)
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```
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**外键：**
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```sql
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CONSTRAINT fk_scores_student FOREIGN KEY (sid) REFERENCES students(id) ON DELETE CASCADE ON UPDATE CASCADE
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```
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> 删除学生时，其所有成绩记录自动级联删除。
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---
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### 3.5 employment — 就业表
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| 字段名 | 类型 | 约束 | 说明 |
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|--------|------|------|------|
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| id | INT | PK, AUTO_INCREMENT | 主键 |
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| sid | INT | UNIQUE, FK→students.id | 学生 ID（一对一） |
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| class_id | INT | NOT NULL, INDEX | 所属班级 ID |
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| employment_open_time | DATETIME | NULL | 就业开放时间 |
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| offer_recived_time | DATETIME | NULL | Offer 下发时间 |
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| employment_company | VARCHAR(50) | NULL | 就业公司 |
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| employment_salary | DECIMAL(20,5) | NULL | 就业薪资（月薪） |
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| create_time | DATETIME | NOT NULL | 创建时间 |
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| update_time | DATETIME | NOT NULL | 更新时间 |
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| is_deleted | BOOLEAN | DEFAULT FALSE | 软删除标志 |
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| delete_time | DATETIME | NULL | 删除时间 |
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**索引：**
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```sql
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PRIMARY KEY (id),
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UNIQUE KEY uk_sid (sid), -- 一名学生只允许一条就业记录
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KEY idx_class_id (class_id),
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KEY idx_class_deleted (class_id, is_deleted) -- 复合索引，优化班级就业统计
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```
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**外键：**
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```sql
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CONSTRAINT fk_employment_student FOREIGN KEY (sid) REFERENCES students(id) ON DELETE CASCADE ON UPDATE CASCADE,
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CONSTRAINT fk_employment_class FOREIGN KEY (class_id) REFERENCES classes(id) ON DELETE RESTRICT ON UPDATE CASCADE
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```
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---
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## 4. 完整 DDL（可直接执行）
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```sql
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CREATE DATABASE IF NOT EXISTS sms
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CHARACTER SET utf8mb4
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COLLATE utf8mb4_unicode_ci;
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USE sms;
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-- ==================== teachers ====================
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CREATE TABLE IF NOT EXISTS teachers (
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id INT AUTO_INCREMENT PRIMARY KEY,
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num VARCHAR(30) NOT NULL COMMENT '教师编号',
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name VARCHAR(30) NOT NULL DEFAULT '' COMMENT '姓名',
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age INT NOT NULL DEFAULT 18 COMMENT '年龄',
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sex INT NOT NULL DEFAULT 0 COMMENT '性别：0未知 1男 2女',
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home_place VARCHAR(50) NULL COMMENT '家乡',
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college VARCHAR(50) NULL COMMENT '毕业院校',
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specialty VARCHAR(50) NULL COMMENT '专业',
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enrollment_time DATETIME NULL COMMENT '入学时间',
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graduate_time DATETIME NULL COMMENT '毕业时间',
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education VARCHAR(50) NULL COMMENT '学历',
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work_experience TEXT NULL COMMENT '工作经验',
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coach_area VARCHAR(50) NULL COMMENT '教学方向：应用/项目/算法',
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create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
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update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
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is_deleted TINYINT(1) NOT NULL DEFAULT 0,
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delete_time DATETIME NULL,
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UNIQUE KEY uk_tnum (num),
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KEY idx_num (num)
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) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='教师表';
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-- ==================== classes ====================
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CREATE TABLE IF NOT EXISTS classes (
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id INT AUTO_INCREMENT PRIMARY KEY,
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num VARCHAR(30) NOT NULL COMMENT '班级编号',
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name VARCHAR(30) NOT NULL COMMENT '班级名称',
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class_start_time DATETIME NULL COMMENT '开课时间',
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head_teacher_id INT NULL COMMENT '班主任ID',
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coach_teacher_id INT NULL COMMENT '授课老师ID',
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tutor_teacher_id INT NULL COMMENT '助教老师ID',
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create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
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update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
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is_deleted TINYINT(1) NOT NULL DEFAULT 0,
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delete_time DATETIME NULL,
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UNIQUE KEY uk_class_num (num),
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KEY idx_head_teacher (head_teacher_id),
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KEY idx_coach_teacher (coach_teacher_id),
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KEY idx_tutor_teacher (tutor_teacher_id)
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) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='班级表';
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ALTER TABLE classes
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ADD CONSTRAINT fk_classes_head_teacher FOREIGN KEY (head_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE,
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ADD CONSTRAINT fk_classes_coach_teacher FOREIGN KEY (coach_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE,
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ADD CONSTRAINT fk_classes_tutor_teacher FOREIGN KEY (tutor_teacher_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE;
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-- ==================== students ====================
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CREATE TABLE IF NOT EXISTS students (
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id INT AUTO_INCREMENT PRIMARY KEY,
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num VARCHAR(30) NOT NULL COMMENT '学生编号',
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name VARCHAR(30) NOT NULL DEFAULT '' COMMENT '姓名',
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age INT NOT NULL DEFAULT 18 COMMENT '年龄',
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sex INT NOT NULL DEFAULT 0 COMMENT '性别：0未知 1男 2女',
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home_place VARCHAR(50) NULL COMMENT '家乡',
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college VARCHAR(50) NULL COMMENT '毕业院校',
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specialty VARCHAR(50) NULL COMMENT '专业',
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enrollment_time DATETIME NULL COMMENT '入学时间',
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graduate_time DATETIME NULL COMMENT '毕业时间',
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education VARCHAR(50) NULL COMMENT '学历',
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class_id INT NOT NULL DEFAULT 0 COMMENT '所属班级ID',
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advisor_id INT NULL COMMENT '顾问老师ID',
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create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
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update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
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is_deleted TINYINT(1) NOT NULL DEFAULT 0,
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delete_time DATETIME NULL,
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UNIQUE KEY uk_snum (num),
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KEY idx_class_id (class_id),
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KEY idx_advisor_id (advisor_id),
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KEY idx_class_deleted (class_id, is_deleted)
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) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='学生表';
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ALTER TABLE students
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ADD CONSTRAINT fk_students_class FOREIGN KEY (class_id) REFERENCES classes(id) ON DELETE RESTRICT ON UPDATE CASCADE,
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ADD CONSTRAINT fk_students_advisor FOREIGN KEY (advisor_id) REFERENCES teachers(id) ON DELETE SET NULL ON UPDATE CASCADE;
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-- ==================== scores ====================
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CREATE TABLE IF NOT EXISTS scores (
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id INT AUTO_INCREMENT PRIMARY KEY,
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sid INT NOT NULL COMMENT '学生ID',
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num VARCHAR(30) NOT NULL COMMENT '考核序次',
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score DECIMAL(10,2) NOT NULL COMMENT '分数',
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create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
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update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
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is_deleted TINYINT(1) NOT NULL DEFAULT 0,
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delete_time DATETIME NULL,
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UNIQUE KEY uk_sid_score (sid, num),
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KEY idx_sid (sid)
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) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='成绩表';
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ALTER TABLE scores
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ADD CONSTRAINT fk_scores_student FOREIGN KEY (sid) REFERENCES students(id) ON DELETE CASCADE ON UPDATE CASCADE;
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-- ==================== employment ====================
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CREATE TABLE IF NOT EXISTS employment (
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id INT AUTO_INCREMENT PRIMARY KEY,
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sid INT NOT NULL COMMENT '学生ID',
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class_id INT NOT NULL COMMENT '班级ID',
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employment_open_time DATETIME NULL COMMENT '就业开放时间',
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offer_recived_time DATETIME NULL COMMENT 'Offer下发时间',
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employment_company VARCHAR(50) NULL COMMENT '就业公司',
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employment_salary DECIMAL(20,5) NULL COMMENT '就业薪资（月薪）',
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create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
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update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
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is_deleted TINYINT(1) NOT NULL DEFAULT 0,
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delete_time DATETIME NULL,
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UNIQUE KEY uk_sid (sid),
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KEY idx_class_id (class_id),
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KEY idx_class_deleted (class_id, is_deleted)
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) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='就业表';
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ALTER TABLE employment
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ADD CONSTRAINT fk_employment_student FOREIGN KEY (sid) REFERENCES students(id) ON DELETE CASCADE ON UPDATE CASCADE,
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ADD CONSTRAINT fk_employment_class FOREIGN KEY (class_id) REFERENCES classes(id) ON DELETE RESTRICT ON UPDATE CASCADE;
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```
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---
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## 5. 索引设计说明
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| 表 | 索引名 | 类型 | 字段 | 优化场景 |
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|----|--------|------|------|----------|
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| students | uk_snum | 唯一 | num | 按学号精确查询 |
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| students | idx_class_id | 普通 | class_id | 按班级查学生列表 |
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| students | idx_advisor_id | 普通 | advisor_id | 按顾问查学生 |
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| students | idx_class_deleted | 联合 | (class_id, is_deleted) | 查某班未删除学生（覆盖常见过滤） |
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| classes | uk_class_num | 唯一 | num | 按班级编号精确查询 |
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| classes | idx_head_teacher | 普通 | head_teacher_id | 按班主任查班级 |
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| scores | uk_sid_score | 唯一 | (sid, num) | 防止重复录入，加速组合查询 |
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| scores | idx_sid | 普通 | sid | 按学生查成绩 |
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| employment | uk_sid | 唯一 | sid | 保证一人一条就业记录 |
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| employment | idx_class_id | 普通 | class_id | 按班级统计就业 |
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| employment | idx_class_deleted | 联合 | (class_id, is_deleted) | 班级就业统计过滤已删除记录 |
|
||
|
||
---
|
||
|
||
## 6. 数据字典表（V2.0 规划）
|
||
|
||
```sql
|
||
CREATE TABLE IF NOT EXISTS dict_items (
|
||
id INT AUTO_INCREMENT PRIMARY KEY,
|
||
dict_type VARCHAR(50) NOT NULL COMMENT '字典类型：sex, education, college, specialty, coach_area',
|
||
dict_code VARCHAR(50) NOT NULL COMMENT '字典编码，业务表存储的值',
|
||
dict_label VARCHAR(100) NOT NULL COMMENT '显示名称',
|
||
sort_order INT NOT NULL DEFAULT 0 COMMENT '排序权重',
|
||
is_enabled TINYINT(1) NOT NULL DEFAULT 1 COMMENT '是否启用',
|
||
create_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
|
||
update_time DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
|
||
is_deleted TINYINT(1) NOT NULL DEFAULT 0,
|
||
delete_time DATETIME NULL,
|
||
UNIQUE KEY uk_type_code (dict_type, dict_code),
|
||
KEY idx_type (dict_type)
|
||
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='通用字典表';
|
||
|
||
-- 初始数据
|
||
INSERT INTO dict_items (dict_type, dict_code, dict_label, sort_order) VALUES
|
||
('sex', '0', '未知', 1),
|
||
('sex', '1', '男', 2),
|
||
('sex', '2', '女', 3),
|
||
('education','bachelor', '本科', 1),
|
||
('education','master', '硕士', 2),
|
||
('education','phd', '博士', 3),
|
||
('coach_area','app', '应用', 1),
|
||
('coach_area','project', '项目', 2),
|
||
('coach_area','algorithm','算法', 3);
|
||
```
|
||
|
||
**引用方式（应用层 JOIN）：**
|
||
```sql
|
||
-- 查询学生时关联字典获取可读名称
|
||
SELECT s.*,
|
||
d_sex.dict_label AS sex_label,
|
||
d_edu.dict_label AS education_label
|
||
FROM students s
|
||
LEFT JOIN dict_items d_sex ON d_sex.dict_type='sex' AND d_sex.dict_code=CAST(s.sex AS CHAR)
|
||
LEFT JOIN dict_items d_edu ON d_edu.dict_type='education' AND d_edu.dict_code=s.education
|
||
WHERE s.is_deleted=0;
|
||
```
|
||
|
||
---
|
||
|
||
## 7. 历史数据归档策略（V3.0 规划）
|
||
|
||
当数据量达到千万级时，考虑以下归档方案：
|
||
|
||
| 策略 | 适用场景 | 说明 |
|
||
|------|----------|------|
|
||
| 分区表（PARTITION BY RANGE） | 按年份归档 | 对 `create_time` 做范围分区，老分区可迁移至冷存储 |
|
||
| 归档表（_history 后缀） | 毕业生数据 | 将已毕业学生的成绩/就业记录移入 `students_history` 等归档表 |
|
||
| 分库分表 | 超大规模 | 按 `class_id` 哈希分片，需引入 ShardingSphere 或应用层分片 |
|
||
|
||
**归档判断条件：**
|
||
- 学生 `graduate_time` 距今超过 2 年
|
||
- 或主动标记为"已归档"状态
|