这是一段MySQL数据库代码,请生成它的E/R图
时间: 2024-12-29 11:34:14 浏览: 5
根据提供的MySQL数据库代码,以下是该数据库的实体关系(E/R)图描述:
### 实体(Entities)
1. **tb_admin** (管理员)
- 属性: `id`, `username`, `password`, `tele`
2. **tb_user** (用户)
- 属性: `id`, `username`, `password`, `name`, `gender`, `numb`, `tele`, `idnum`
3. **tb_room** (房间)
- 属性: `id`, `numb`, `type`, `price`, `status`
4. **tb_previewroom** (预定)
- 属性: `id`, `userid`, `numb`, `roomid`, `createtime`, `count`
5. **tb_ruzhu** (入住办理)
- 属性: `id`, `userid`, `numb`, `roomid`, `intime`, `jiwan`, `price`, `createtime`
6. **tb_goods** (客房消费品)
- 属性: `id`, `name`, `price`, `count`
7. **tb_otherservice** (其他服务)
- 属性: `id`, `userid`, `type`, `content`, `createtime`
8. **tb_baojie** (保洁)
- 属性: `id`, `username`, `password`, `name`, `gender`, `numb`, `tele`, `idnum`
### 关系(Relationships)
1. **tb_previewroom** (预定) 与 **tb_user** (用户)
- 外键: `userid` 引用 `tb_user.id`
2. **tb_previewroom** (预定) 与 **tb_room** (房间)
- 外键: `roomid` 引用 `tb_room.id`
3. **tb_ruzhu** (入住办理) 与 **tb_user** (用户)
- 外键: `userid` 引用 `tb_user.id`
4. **tb_ruzhu** (入住办理) 与 **tb_previewroom** (预定)
- 外键: `numb` 引用 `tb_previewroom.numb`
5. **tb_ruzhu** (入住办理) 与 **tb_room** (房间)
- 外键: `roomid` 引用 `tb_room.id`
6. **tb_otherservice** (其他服务) 与 **tb_user** (用户)
- 外键: `userid` 引用 `tb_user.id`
### 唯一索引和字段限制
- **tb_admin**
- `username` 唯一索引
- **tb_user**
- `username` 唯一索引
- `name` 唯一索引
- `numb` 唯一索引
- `gender` 字段限制: `男`, `女`
- **tb_room**
- `numb` 唯一索引
- `type` 字段限制: `单人床`, `大床房`, `双人房`, `三人房`
- `status` 字段限制: `空房`, `脏房`, `净房`
- `username` 唯一索引
- `name` 唯一索引
- `numb` 唯一索引
- `gender` 字段限制: `男`, `女`
### E/R 图示例
```plaintext
+-----------------+ +-----------------+ +-----------------+
| tb_admin | | tb_user | | tb_room |
+---+ +-----------------+ +-----------------+
| id | | id | | id |
| username (unique)| | username (unique)| | numb (unique) |
| password | | password | | type (check) |
| tele | | name (unique) | | price |
+-----------------+ | gender (check) | | status (check) |
| numb (unique) | +-----------------+
| tele |
| idnum |
+--+ +-----------------+
| tb_previewroom | | tb_ruzhu | | tb_goods |
+-----------------+ +-----------------+ +-----------------+
| id | | id | | id |
| userid | | userid | | name (unique) |
| numb | | numb | | price |
| roomid | | roomid | | count |
| createtime | | intime | +-----------------+
| count | | jiwan |
+-----------------+ | price |
| createtime |
+--+
+-----------------+ +-----------------+
| tb_otherservice | | tb_baojie |
+---+
| id | | id |
| userid | | username (unique)|
| type (check) | | password |
| content | | name (unique) |
| createtime | | gender (check) |
+-----------------+ | numb (unique) |
| tele |
| idnum |
+-----------------+
```
### 关系表示
- `tb_previewroom.userid -> tb_user.id`
- `tb_previewroom.roomid -> tb_room.id`
- `tb_ruzhu.userid -> tb_user.id`
- `tb_ruzhu.numb -> tb_previewroom.numb`
- `tb_ruzhu.roomid -> tb_room.id`
- `tb_otherservice.userid -> tb_user.id`
希望这个E/R图能帮助你更好地理解数据库结构。如果有任何进一步的问题或需要更详细的图表,请告诉我!
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