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                            # DBMS 中的關系模型

> 原文： [https://beginnersbook.com/2015/04/relational-model-in-dbms/](https://beginnersbook.com/2015/04/relational-model-in-dbms/)

在關系模型中，數據和關系由相互關聯的表的集合表示。每個表都是一組列和行，其中列表示實體的屬性，行表示記錄。

**樣本關系模型**：具有 3 列和 4 個記錄的學生表。

**表：學生**

| `Stu_Id` | `Stu_Name` | `Stu_Age` |
| --- | --- | --- |
| 111 | Ashish | 23 |
| 123 | Saurav | 22 |
| 169 | Lester | 24 |
| 234 | Lou | 26 |

**表：課程**

| `Stu_Id` | `COURSE_ID` | `COURSE_NAME` |
| --- | --- | --- |
| 111 | C01 | Science |
| 111 | C02 | DBMS |
| 169 | C22 | Java |
| 169 | C39 | Computer Networks |

這里`Stu_Id`，`Stu_Name`和`Stu_Age` 是表`Student`的屬性，`Stu_Id`，`Course_Id`和`Course_Name`是`Course`表的屬性。具有值的行是記錄（通常稱為元組）。
                    
                
        
                
            
        
                
    
                
    
                
        
                
    
                

                







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